Official Transcript of Proceedings

NUCLEAR REGULATORY COMMISSION

Title: Advisory Committee on Reactor Safeguards

Docket Number: n/a

Location: Rockville, Maryland

Date: September 8, 2011

Work Order No.: NRC-1108 Pages 1-328

NEAL R. GROSS AND CO., INC.

Court Reporters and Transcribers

1323 Rhode Island Avenue, N.W.

Washington, D.C. 20005

(202) 234-4433
DISCLAIMER

UNITED STATES NUCLEAR REGULATORY COMMISSION’S 

ADVISORY COMMITTEE ON REACTOR SAFEGUARDS

The contents of this transcript of the proceeding of the United States Nuclear 

Regulatory Commission Advisory Committee on Reactor Safeguards, as reported 

herein, is a record of the discussions recorded at the meeting. 

This transcript has not been reviewed, corrected, and edited, and it may contain 

inaccuracies. 
1

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 UNITED STATES OF AMERICA

2 NUCLEAR REGULATORY COMMISSION

3 + + + + +

4 586TH MEETING

5 ADVISORY COMMITTEE ON REACTOR SAFEGUARDS

6 (ACRS)

7 + + + + +

8 THURSDAY

9 SEPTEMBER 8, 2011

10 + + + + +

11 ROCKVILLE, MARYLAND

12 + + + + +

13 The Advisory Committee met at the

14 Nuclear Regulatory Commission, Two White Flint

15 North, Room T2B1, 11545 Rockville Pike, at 8:30

16 a.m., Said Abdel-Khalik, Chairman, presiding.

17 COMMITTEE MEMBERS:

18 SAID ABDEL-KHALIK, Chairman

19 J. SAM ARMIJO, Vice Chairman

20 JOHN W. STETKAR, Member-at-Large

21 SANJOY BANERJEE, Member

22 DENNIS C. BLEY, Member

23 CHARLES H. BROWN, JR., Member

24 MICHAEL L. CORRADINI, Member

25 DANA A. POWERS, Member
2

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 HAROLD B. RAY, Member

2 JOY REMPE, Member

3 MICHAEL T. RYAN, Member

4 WILLIAM J. SHACK, Member

5 JOHN D. SIEBER, Member

6 GORDON R. SKILLMAN, Member

7

8 NRC STAFF PRESENT:

9 EDWIN M. HACKETT, Executive Director, ACRS

10 ANTONIO DIAZ, Designated Federal Official

11 PERRY BUCKBERG

12 ANDREW CARRERA

13 AMY CUBBAGE

14 DANIEL DORMAN

15 ANDRZEJ DROZD

16 DON DUBE

17 DAVID ESH

18 JACK GROBE

19 JOHN HONCHARIK

20 DEBORAH JACKSON

21 STEVEN JONES

22 JOHN LABINSKY

23 EILEEN McKENNA

24 PRAVIN PATEL

25 SIMON C.F. SHENG
3

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 ALSO PRESENT:

2 TOD BAKER, Westinghouse

3 KENT BONADIO, Westinghouse

4 BRAD CARPENTER, Westinghouse

5 MIKE CORLETTI, Westinghouse

6 ADRIAN P. HEYMER, Nuclear Energy Institute

7 TOM KINDRED, Westinghouse

8 RICK OFSTUN, Westinghouse

9 SUSAN G. STERRETT, Carnegie-Mellon University*

10 LEO TUNON-SANJUR, Westinghouse

11 ROLF ZIESING, Westinghouse

12 *Present via telephone

13

14

15

16

17

18

19

20

21

22

23

24

25
4

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 A G E N D A

2

3 OPENING REMARKS BY THE ACRS CHAIRMAN ...... 5

4 NEAR-TERM TASK FORCE REPORT REGARDING THE

5 EVENTS AT THE FUKUSHIMA DAI-ICHI SITE

6 IN JAPAN ................. 7

7 BREAK . . . . . . . . . . . . . . . . . . . . . . 98

8 TECHNICAL BASIS AND RULEMAKING LANGUAGE 

9 ASSOCIATED WITH LW-LEVEL WASTE DISPOSAL

10 AND SITE-SPECIFIC ANALYSIS . . . . . . . . 99

11 LUNCH . . . . . . . . . . . . . . . . . . . . . 170

12 SAFETY EVALUATION REPORT ASSOCIATED WITH

13 REVISION 19 OF THE AP1000 DESIGN

14 CONTROL DOCUMENT AMENDMENT . . . . . . . 171

15 BREAK.......................

16 DRAFT FINAL REVISION 2 TO REGULATORY GUIDE

17 1.115, "PROTECTION AGAINST TURBINE 

18 MISSILES" ..................

19 PREPARATION OF ACRS REPORTS ............

20

21

22

23

24

25
5

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 P R O C E E D I N G S

2 (8:35:51 a.m.)

3 CHAIRMAN ABDEL-KHALIK: The meeting will

4 now come to order.

This is the first day of the 586th 5 Meeting

6 of the Advisory Committee on Reactor Safeguards.

7 During today's meeting, the Committee will consider

8 the following.

9 One, Near-Term Task Force Report regarding

10 the events at the Fukushima Dai-Ichi Site in Japan.

11 Two, Technical Basis and Rulemaking Language

12 associated with low-level waste disposal and site

13 specific analysis. Three, Safety Evaluation Report

14 associated with Revision 19 of the AP1000 Design

15 Control Document Amendment. Four, Draft Final

16 Revision 2 to Reg Guide 1.115, "Protection Against

17 Turbine Missiles." And, five, preparation of ACRS

18 reports.

19 This meeting is being conducted in

20 accordance with the provisions of the Federal Advisory

21 Committee Act. Dr. Antonio Diaz is the Designated

22 Federal Official for the initial portion of the

23 meeting.

24 Portions of the session dealing with the

25 Safety Evaluation Report associated with Revision 19
6

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 of the AP1000 Design Control Document Amendment may be

2 closed in order to protect information designated as

3 proprietary by Westinghouse.

4 The Nuclear Energy Institute has submitted

5 written comments on the Near-Term Task Force Report

6 regarding the events at the Fukushima Dai-Ichi site in

7 Japan. Mr. Adrian Heymer from the Nuclear Energy

8 Institute has also requested time to make an oral

9 statement regarding this session.

10 In addition, Dr. Susan Sterrett has

11 requested time to make an oral statement regarding the

12 session on the SER associated with Revision 19 of the

13 AP1000 DCD Amendment.

14 There will be a phone bridge line. To

15 preclude interruption of the meeting, the phone will

16 be placed in a listen-in mode during the presentations

17 and Committee discussion. At the appropriate time,

18 the phone will be open to allow Dr. Sterrett to

19 provide her comments to the Committee.

20 A transcript of portions of the meeting is

21 being kept, and it is requested that the speakers use

22 one of the microphones, identify themselves, and speak

23 with sufficient clarity and volume so that they can be

24 readily heard.

25 We will now move to the first item on the
7

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 agenda, Near-Term Task Force Report regarding the

2 events at the Fukushima Dai-Ichi site in Japan. And

3 I call on Mr. Jack Grobe to begin the presentation.

4 Jack?

5 MR. GROBE: Thank you very much.

6 We certainly appreciated the opportunity

7 a couple of weeks ago to spend several hours with the

8 Subcommittee. The slides we've prepared today are a

9 very brief set of slides that overarch or provide the

10 overarching recommendations. We look forward to the

11 questions that you may have come up with studying our

12 report in the last two weeks, and new questions that

13 might come up during the course of the meeting. Next

14 slide, please.

15 Again, the Task Force was led by Charlie

16 Miller, who is on the golf course somewhere. He's

17 retired. Nathan Sanfilippo is not here with us today.

18 He's up meeting with Region I in the State of New

19 Jersey on Fukushima Lessons Learned, and Gary Holahan

20 is trying to license new reactors. He had a number of

21 important meetings that he couldn't reschedule, so I

22 apologize for those two individuals not being with us,

23 but the rest of the Task Force is here today.

24 High-level summary, the Near-Term Task

25 Force concluded that a similar sequence of events is
8

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 unlikely to occur in the United States that occurred

2 at the Fukushima Dai-Ichi Nuclear Power Plant. And we

3 have existing mitigating measures here in the United

4 States that provide additional capability, and reduce

5 the likelihood of core damage if they remain available

6 during the event.

7 The Task Force further concluded that

8 there's no imminent risk, and what that means is

9 there's no need to take action to curtail operation of

10 reactors or impose immediate changes to the licensing

11 structure for the reactors. However, there's a number

12 of recommendations; 12 overarching recommendations to

13 enhance safety, including some near-term interim

14 actions.

15 The 12 overarching recommendations, the

16 first one -- 

17 CHAIRMAN ABDEL-KHALIK: Jack, before we get

18 into the details of the recommendations, let me just

19 ask a big picture question.

20 Would you agree with the statement that

21 the recommendations of the Task Force were not based

22 on detailed evaluation of the progression of the

23 Fukushima accident; instead, they were based on facts

24 that became self-evident to knowledgeable individuals

25 as a result of the Fukushima accident.
9

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. GROBE: I look for my comrades here to

2 provide additional insights, but I would say it's

3 between those two. We certainly had people on the

4 ground in Japan, and we have had since the event

5 occurred. We met with those people as they came back

6 from Japan to gain insights. We asked questions

7 regarding, for example, specifically the functioning

8 of the hardened vents, and got detailed information

9 back from our team in Japan on how the vents were

10 designed at Fukushima, and the attempts that they

11 made. So, it was somewhere in between there.

12 Clearly, at this point in time, we do not

13 have a complete understanding of the core progression,

14 the damage progression in the core, or the sequences

15 that preceded that, but we have a lot of information.

16 One of the recommendations, not one of the

17 overarching recommendations, but a recognition in the

18 report is that that work is ongoing collecting that

19 information, and that there could be additional

20 lessons to learn as we gain more information. But the

21 Near-Term Task Force felt confident that the basis of

22 these recommendations had sufficient foundation both

23 in what occurred in Japan, as well as thorough

24 examination of how we regulate those particular

25 aspects.
10

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 CHAIRMAN ABDEL-KHALIK: Okay. So, let me

2 ask you a specific question then that follows from the

3 first. And you touched on it in the last two

4 sentences.

5 Would acquisition of more detailed

6 information regarding the progression of the Fukushima

7 accident negate or render invalid any of the Task

8 Force's recommendations?

9 MR. GROBE: It's difficult to project what

10 might happen, but I think the Task Force members feel

11 highly confident that that's unlikely. Is that -- 

12 MR. DORMAN: Yes, I would agree. As we

13 developed those recommendations, I think we had a

14 consensus that it was unlikely that further detail of

15 the progression of the events at Fukushima, it was

16 unlikely that those would change the recommendations

17 that we made.

18 MR. GROBE: And specifically in the area of

19 hydrogen control. We could have made recommendations,

20 and we had a lot of thoughts and ideas, but our

21 ultimate conclusion was we really don't understand

22 enough about how hydrogen transported between

23 structures to make recommendations at this point in

24 time.

25 CHAIRMAN ABDEL-KHALIK: But the specific
11

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 recommendations contained within your report, you

2 believe that those remain valid.

3 MR. GROBE: Those are solid, yes.

4 CHAIRMAN ABDEL-KHALIK: Even if one were to

5 acquire additional information regarding the details

6 of the progression of the event at Fukushima.

7 MR. GROBE: That's correct.

8 MR. DORMAN: That's our expectation.

9 MR. GROBE: Yes.

10 CHAIRMAN ABDEL-KHALIK: Okay. So, one may

11 gain additional insights that may lead to additional

12 recommendations, if one were to know more about what

13 happened.

14 MR. GROBE: Yes.

15 MR. DORMAN: Yes.

16 CHAIRMAN ABDEL-KHALIK: Okay, thank you.

17 MR. GROBE: Okay. Twelve overarching

18 recommendations. One concerns a Policy Statement, and

19 the Commission has requested that the Staff provide a

20 detailed paper in 18 months providing options on that

21 Policy Statement recommendation.

22 There's a number of rulemaking

23 recommendations in areas where the Task Force felt

24 that a lasting regulation was necessary. A number of

25 orders that either form interim steps or orders
12

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 imposing requirements where rulemaking is not

2 necessary, and several Staff actions. 

3 There were four longer-term studies, and

4 we just mentioned one of them, one of them was

5 hydrogen, but these were situations where the Near6 Term Task Force did not believe we had sufficient

7 information to make a recommendation that was well

8 founded, and it required additional study. That

9 doesn't mean that you wait four years to start the

10 evaluation. You start the evaluation now, but it's

11 longer-term. We need more information. Next slide.

12 The focus of the Steering Committee -- not

13 the Steering Committee, the Task Force was to examine

14 -- we examined our regulatory framework, and

15 identified that the regulatory framework is founded on

16 a defense-in-depth concept. And that defense-in-depth

17 concept has been applied in a number of different ways

18 in different parts of our regulations. But the one

19 that seemed appropriate and lasting for us was the

20 concept of protection, mitigation, and preparedness.

21 So, that was the way in which we structured our

22 recommendations and our study. And, of course, we also

23 looked internal at ourselves, at our own programs. 

24 So, the first recommendation had to do

25 with the framework. This was a framework for beyond
13

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 -- what we currently call beyond -- 

2 CHAIRMAN ABDEL-KHALIK: I'm sorry to

3 interrupt, but let's just get the terminology

4 straight. 

5 What do you mean exactly by the words

6 "near-term", and "long-term?" Do you have a time line

7 that that translates to?

8 MR. GROBE: Well, in the Tasking Memorandum

9 that came from the Commission, there was an

10 expectation of the time line, and that was that the

11 near-term would be done in 90 days, and the long-term

12 would be six months after that.

13 The 90-day near-term report took about 120

14 days, and I believe longer-term -- 

15 CHAIRMAN ABDEL-KHALIK: Well, my question

16 pertains not to the preparation of the reports, but

17 completion of the actions designated as near-term --

18 MR. GROBE: Oh, I'm sorry.

19 CHAIRMAN ABDEL-KHALIK: -- or the

20 actions designated as long-term. 

21 MR. GROBE: The -- I think the Task Force

22 was very aware of the Agency's past practices in the

23 area of following up on major events. We've done a

24 good deal of time at the beginning of our work

25 studying how the Agency responded, and the federal
14

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 government, quite frankly, responded to Three Mile

2 Island. We also studied how the Agency responded to

3 9/11. 

4 Our conclusion from that was that we have

5 to insure that we are very careful and methodical in

6 how we approach these recommendations, and to insure

7 that we don't overreach, and also to insure that if we

8 cause action to be taken to change our regulations or

9 to modify the plants and the way they operate that

10 that is the right action, and it doesn't have to be

11 redone in the future.

12 For that reason, there's a significant

13 emphasis and recognition on the need for engagement

14 with the industry and our stakeholders to clarify in

15 some areas of these recommendations exactly what would

16 be the best approach in implementing the

17 recommendation. That recommendation was fairly high18 level.

19 A good example of that, again, is the

20 hardened vents. There's a clear outcome from Fukushima

21 and from studying how we implemented hardened vents.

22 There's a clear conclusion; two things. One is we

23 should have a requirement, it shouldn't just be a

24 voluntary situation. And secondly, we need to focus

25 more attention on the reliability of the hardened
15

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 vents, and that reliability has to do with passive

2 function versus active function, it has to do with the

3 ability to function without AC power, has to do with

4 the accessibility of the valves, the location of the

5 valves, things of that nature.

6 So, we should not -- the Commission should

7 not independently define exactly how those systems

8 should be designed, we should collect information on

9 the best thinking. So, the timing for each of these

10 regulations, excuse me, each of these recommendations

11 would be dependent upon the level and need for

12 engagement with folks like yourself, the industry, our

13 external stakeholders. And it should be methodical

14 and take into consideration all of those appropriate

15 points of view. So, there isn't -- that was a long

16 answer.

17 (Simultaneous speech.)

18 MR. GROBE: Yes, there isn't a specific

19 time frame other than there's certain recommendations

20 that should be begun, that should be initiated very

21 promptly, meaning today, within the next couple of

22 months.

23 CHAIRMAN ABDEL-KHALIK: Let me give you a

24 reference point. The Koreans have come up with a list

25 of 50 items that they need to implement at their
16

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 plants, and they define near-term as actions that must

2 be concluded by the end of 2012, and they define

3 intermediate and long-term actions as things that must

4 be completed in the years 2013 to 2015, and I

5 emphasize the word "completed." Is that consistent

6 with your understanding and/or expectations?

7 MR. GROBE: We have not provided that kind

8 of context on our recommendations. I would think some

9 of the recommendations can be completed in a matter of

10 months, not years. I believe other recommendations are

11 going to take a couple of years to complete, and there

12 are some recommendations that will take multiple years

13 to complete. So, we did not parse the recommendations

14 in that way. 

15 I don't know -- I haven't studied the 50

16 recommendations that Korea used, but it's entirely

17 likely that they can parse them that way. We did not

18 do that.

19 MS. CUBBAGE: In the context of our report,

20 near-term was were areas where we felt we could come

21 up with a specific recommendation in the near-term,

22 and then the long-term evaluations would be passed to

23 the longer-term evaluation. That's the near24 term/long-term context for our report, but more

25 details will be coming out with the Commission papers
17

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 that are coming due soon.

2 (Simultaneous speech.)

3 CHAIRMAN ABDEL-KHALIK: So near versus

4 long-term in your context pertains to when the actions

5 are to be defined rather than when they are to be

6 completed.

7 MR. GROBE: Yes. And that's not how we

8 chose to define it, that's the Tasking Memorandum that

9 we received from the Commission.

10 MR. DORMAN: I think we also -- the six of

11 us were not in a position to make statements

12 concerning availability of NRC or industry resources

13 to implement these things. We were cognizant of the

14 time frames of our normal processes, and we recognized

15 that rulemakings typically take several years to

16 accomplish to the point of a final rule. And then

17 depending on the complexity of implementation may take

18 a full operating cycle to achieve implementation. So,

19 that's the multiple years Jack was referring to, we

20 were looking at some of those things as potentially

21 four to six years out before they get completed, which

22 is why in several cases we recommended that in the

23 interim there are actions that could be taken through

24 orders that could be implemented in the 12 to 18-month

25 time frame, or even less, that could provide an
18

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 enhanced margin of safety, while that process runs its

2 course. So, we have a general plot of time lines, but

3 the Agency's Long-Term Steering Committee, and

4 probably in the 45-day paper that's due to the

Commission October 3rd 5 will have more of a discussion

6 of characterization and time lines going forward.

7 CHAIRMAN ABDEL-KHALIK: Thank you. 

8 MR. GROBE: Okay. Recommendation 1 was to

9 enhance the framework. The focus of this was two10 fold. The principal focus was the fact that we have

11 these concepts that we currently call beyond design

12 basis, and that's founded in the regulations and the

13 regulatory framework that was established in the `60s

14 and `70s where we have a number of design basis

15 accidents, and we've identified through risk analysis

16 and further insights in the `70s, `80s, `90s that

17 things like station blackout, like anticipated

18 transient without scram, these are beyond design basis

19 events that require our attention. And the

20 Commission's description, its Policy Statements do not

21 deal well with those concepts. 

22 And we felt that it would be beneficial to

23 both the predictability and the clarity of our

24 regulations, as well as the ability for our licensees

25 to understand our regulations, and to be able to
19

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 operate within them in a reliable fashion from a

2 business perspective, that we should have a more -- we

3 should have more clarity in our regulatory framework

4 addressing these areas.

5 Again, the Commission directed the Staff

6 to study this issue and bring forward a clear

7 recommendation in 18 months, and that's on our plate.

8 That's a tasking for the Staff.

9 MEMBER CORRADINI: So, can we just take

10 those two special events which are now in some sense

11 regulated kind of in a gray area between design basis

12 and beyond design basis. So, those two that you just

13 mentioned as an example, one possible outcome of this

14 enhancement might be that within certain rules and

15 recommendations they would fall within the design

16 basis, such that SBOs -- 

17 MR. GROBE: No.

18 MEMBER CORRADINI: I'm trying to understand

19 potential eventualities of what you guys are

20 suggesting. That's what I'm -- 

21 MR. GROBE: You guys can jump in here any

22 time, but we weren't suggesting that we expand the

23 design basis. What we were suggesting is that we

24 create this new category called extended design basis.

25 I think those were the words.
20

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER CORRADINI: So, you're going to

2 define the gray region. Is that what -- 

3 MR. GROBE: Yes.

4 MS. CUBBAGE: Define the region and apply

5 it more consistently, and have more guidance on how

6 and when to -- 

7 VICE CHAIRMAN ARMIJO: Yes, it's kind of

8 hard to see the difference between an expanded -- 

9 MR. DORMAN: Let me -- if you take things

10 like ATWS and station blackout and bring them into the

11 design basis as currently defined in Part 50, you

12 incur a set of requirements on those areas that they

13 don't currently have in terms of -- 

14 MEMBER CORRADINI: System safety

15 components.

16 MR. DORMAN: Yes, and QA requirements,

17 Maintenance Rule requirements, and so on.

18 MEMBER CORRADINI: And then we'll see

19 diversity -- 

20 MR. DORMAN: Yes. Our vision was that this

21 extended design basis would have a consistent

22 application of some graded application of those types

23 of measures to things that are applied to low

24 probability but potentially high consequence events,

25 and in a manner that addresses the elements of
21

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 defense-in-depth in a balanced approach so that we're

2 addressing -- for those low probability high

3 consequence events we're addressing protection,

4 mitigation, and emergency response in a balanced

5 manner.

6 MR. GROBE: Now, I want to make it clear,

7 our Recommendation 2.1 regarding seismic and flooding

8 could redefine the design basis events for individual

9 licensees, because it requires them to reevaluate to

10 current day standards.

11 MEMBER CORRADINI: The probable maximum --

12 MEMBER POWERS: Your explanation leaves me

13 very confused. In the design basis we have an

14 accident involving the double-ended guillotine pipe

15 break which has an extraordinarily low probability,

16 very high consequences, and we apply the QA things to

17 that, so which of these gray area things is going to

18 have less than that because its probability is less

19 than the double-ended guillotine pipe break?

20 MR. DORMAN: Actually, one of the things

21 that we talked about in one of our meetings with the

22 Commission on this was the potential that the

23 framework that we proposed would give them a structure

24 in which to address the extremely low probability

25 LOCAs, so that potentially the double-ended guillotine
22

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 could move from design basis to extended design basis

2 under this framework, and be addressed in that

3 context. I think the -- 

4 MEMBER POWERS: Then we might create

5 something called -- like a transition break size for

6 want of a better term.

7 It seems to me that you're running into a

8 problem of creating this gray area because -- in the

9 name of consistency and gradation that it's never

10 going to be consistent unless you do the whole

11 regulatory structure. 

12 MR. GROBE: Actually, there's a tremendous

13 amount of good work in the -- oh, God, what is it

14 called? Yes, thank you, technology neutral regulatory

15 framework. There's a tremendous amount of good work

16 in there, and we should leverage that work into our

17 current regulatory structure for our operating plants.

18 We can't completely rebuild the plants, we

19 can't rebuild the regulatory structure, but we should

20 provide some clarity in these areas so that 50.46(a)

21 has a home, and it is recognized within the context of

22 our framework where it lives.

23 MEMBER CORRADINI: But if I could just

24 restate how you tried to correct me. I want to make

25 sure I get that right, so let's forget about gray or
23

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 black. But this middle region which you're trying to

2 define, your point is that you're defining it there

3 such that things that reside there, and I just picked

4 the two that you mentioned, others could reside there,

5 others could move there, would be using systems and

6 components that may not have the QA stamp of safety7 related that are required for design basis events in

8 all equipment and components that need to be safety9 related to essentially survive and perform there. Is

10 that -- 

11 MR. GROBE: That's the concept.

12 MEMBER CORRADINI: -- the essence of what

13 this area is?

14 MR. GROBE: Yes.

15 MEMBER CORRADINI: Okay. But then it could

16 be that as things roll out from the accident and we

17 learn more and more, certain things that are in the

18 gray region may move into the black region simply

19 because their probability is higher than we expect, or

20 their potential consequences are higher than we

21 suspect. So, I'm just trying to get clear that -- I'm

22 not going to disagree at the moment with what -- I

23 just want to understand what it is, but my point is

24 they could flow either direction in terms of what

25 things will flow in and flow out, because Dana's point
24

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 about -- and I was just thinking things were going to

2 move potentially into a design basis space, or require

3 the backfits such that -- that are safety-related so

4 that I have a higher confidence that things will

5 perform as needed. That's all I'm trying to

6 understand. But I think I get what you define as this

7 gray region.

8 Now let me try the region over here,

9 severe accident. So, what is it about severe accidents

10 that take it out of the gray region? Is there anything

11 but gray and black?

12 MR. GROBE: One of the interesting

13 characteristics of this conversation is that we're

14 debating something that hasn't been clearly defined

15 yet.

16 (Simultaneous speech.)

17 MR. GROBE: It's a very fluid conversation.

18 There's flexibility -- 

19 MEMBER CORRADINI: That's why we enjoy

20 talking about it.

21 MR. GROBE: Yes, exactly.

22 MR. DORMAN: I think in our minds, clearly

23 there is an area beyond the gray area.

24 MEMBER CORRADINI: Okay.

25 MR. DORMAN: But that does not come into
25

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 regulatory control.

2 MEMBER CORRADINI: Okay.

3 MR. DORMAN: So, that in terms of

4 transition points, obviously, you'd need a transition

5 between design basis and extended design basis, and

6 then you'd need a bound on extended design basis.

7 MEMBER CORRADINI: So, can you give me an

8 example that might pop in your personal head about

9 what's out there that doesn't flow into the gray, and

10 doesn't flow in -- like, in other words, I'm trying --

11 I deal in specifics.

12 MS. CUBBAGE: The meteor strike.

13 MR. GROBE: Yes, the meteor strike.

14 MS. CUBBAGE: That is one that -- 

15 MEMBER CORRADINI: That was an easy one.

16 MR. GROBE: That was the easy one. Well,

17 again, without the work that we're going to be doing

18 over the next 18 months it's difficult to get into a

19 really strong debate on the subject.

20 The concept is that the things that are in

21 the beyond design basis are those that have -- that

22 are beyond the design basis, meaning our current

23 definition of design basis, have a lower frequency of

24 occurrence than what we have in our design basis, and

25 have a significant set of consequences associated with
26

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 them. And we use the words that came out of the IEEE

2 -- excuse me, the IAEA standards of cliff edge event.

3 MEMBER CORRADINI: Okay.

4 MR. GROBE: Which is what ATWS is, what

5 station blackout is, cliff edge events.

6 MEMBER CORRADINI: I'm totally with you,

7 because you then mentioned something else. You've

8 mentioned all the good things that I wanted to draw

9 in.

10 So, if I go back to the -- I think it's

11 18.60, the technology neutral framework, there is a

12 figure in there that has frequency and dose. So, in my

13 simple mind the area that's black is where I have

14 potentially high frequency, or potentially high dose,

15 and then I get into this region where things become

16 low enough either in frequency and dose that I then

17 have a different region. 

18 So, is that what the Task Force was

19 thinking about? Is that a visual mechanism that can

20 at least kind of concretize what you're thinking?

21 MR. GROBE: Soften the concept of dose. I

22 don't believe we were talking about Level 3 PRAs dose.

23 What we were talking about was consequences on the

24 reactor.

25 MEMBER CORRADINI: Okay, fine. Thank you
27

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 very much. That helps. Thank you.

2 MR. GROBE: Recommendation 1 -- I'm not

3 done.

4 (Simultaneous speech.)

5 MEMBER-AT-LARGE STETKAR: Something you

6 just said, I'll ask first. You're thinking about the

7 reactor. Why would you not think about measuring risk

8 to public health, which is dose, however I want to

9 characterize how that risk is measured? Why do we

10 retain this notion of core damage frequency as

11 anything -- as the only thing that we're interested

12 in, because we already know that the frequency of core

13 damage, and the frequency of releases are not

14 independent, especially when we extend out to some of

15 these larger -- 

16 MR. GROBE: You can't have release without

17 core damage. Right? But you -- 

18 MEMBER-AT-LARGE STETKAR: But the

19 conditional probability of a release given core damage

20 is not an independent issue for many of your external

21 events.

22 MR. GROBE: We spent quite a bit of time

23 talking about this, and independent -- we were not

24 unaware of the fact that independent of the Task Force

25 there was an ongoing debate in the Commission paper
28

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 that was forwarded on Level 3 PRAs. Our conclusion, I

2 think, was based simply on a practicality concept.

3 We can provide adequate protection to the

4 public health and safety with reasonable confidence

5 without the sophisticated analysis that's necessary

6 for a Level 3 PRA. Level 3 PRA in our opinion when we

7 wrote this report were difficult to perform. They

8 have a lot of variability in them. And from a

9 regulatory perspective, it's more of a practicality

10 argument, and you guys can help me out here if I miss

11 some points, but how much energy do we want to put

12 into refining with some level of specificity the Level

13 3 PRA, and how would we use that to make -- 

14 (Background noise.)

15 MR. GROBE: -- and is it necessary in our

16 current framework? And our conclusion was that it's

17 not necessary. It certainly is interesting, and I

18 think Gary even said it would be fun, but the

19 conclusion that we rendered was that we don't need it

20 today to do what we need to do to protect public

21 health and safety at an appropriate level. Probably

22 different opinions about that.

23 MEMBER-AT-LARGE STETKAR: Absolutely.

24 MR. GROBE: With unlimited resources

25 there's no question that it's something that would
29

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 provide a finer scalpel edge on what we do and how we

2 do it. But the question is, are those the resources

3 that you want to spend?

4 MEMBER-AT-LARGE STETKAR: Yes, and this is

5 certainly not the forum to discuss resources, level of

6 effort.

7 The other question I had, Jack, is you

8 mentioned that Staff will prepare a paper regarding

9 Recommendation 1 sometime over the next 18 months. How

10 fundamental to the near-term recommendations, the

11 scope of the near-term recommendations is this notion

12 of changing fundamental regulatory framework? In

13 other words, you know, as Mike mentioned, it's always

14 easy and interesting to sit around and discuss things

15 as long as they're in the future.

16 Why isn't Recommendation 1 something that

17 we should be working on today internally in the

18 Commission, not put off for 18 months with additional

19 consideration, and five years down the road we'll

20 think about eventually getting around to changing the

21 regulatory framework that will take another decade to

22 do.

23 MR. DORMAN: You used the term "fundamental

24 change," and I want to start by perhaps somewhat

25 challenging the premise that this is a fundamental
30

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 change that we've proposed. 

2 What we proposed to the Commission was

3 that within the framework of the existing 51.09 and

4 the associated criteria for evaluating potential

5 backfits and exceptions to backfit analysis, that the

6 staff has ample guidance and experience with cost7 benefit analyses under 51.09, that with the compliance

8 exception we deal in compliance space through our

9 oversight process all the time. But in the criteria

10 related to adequate protection or potentially

11 redefining the level of protection to be regarded as

12 adequate, clearly those are Commission decisions, but

13 the Staff has virtually no guidance on how to frame a

14 recommendation in that area, what factors to consider,

15 how to apply that.

16 In the context of these low probability

17 high consequence events, what the Task Force proposed

18 was using the defense-in-depth as discussed in the

19 safety goal Policy Statement, and reflected in other

20 international standards as a framework for evaluating

21 these events, and framing a recommendation relative to

22 adequate protection.

23 Now, to go to the more particular

24 question, we applied that framework in evaluating our

25 recommendations. We originally had this --
31

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Recommendation 1 was originally -- that section was

2 originally at the back of our report and we moved it

3 to the front because it was the framework that we used

4 to look at the rest of it.

5 What the Commission has asked the Staff to

6 do looking at our report is to take Recommendation 1

7 out 18 months, and look at the remainder of the

8 recommendations with the framework that we have today.

9 So, that's what the Staff is doing in the 21-day paper

10 and the 45-day paper, is looking at the

11 recommendations that we developed and used in the

12 balanced approach to defense-in-depth that we

13 proposed. And the Staff is looking at those in light

14 of guidance that exists today.

15 So, in terms of do we need to be -- do we

16 need to do this one to be able to get to these, I

17 think that the Staff's answer is generally going to be

18 no, but -- and then the Staff will address to the

19 Commission -- 

20 MEMBER-AT-LARGE STETKAR: But if I

21 understand your answer, you said that this type of

22 framework informed your decisions about the

23 recommendations, and any priorities, for example, that

24 may come out of them. So, this basic notion is

25 something that, indeed, you did use. 
32

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. DORMAN: It is. Having said that, one

2 of the things we looked at, Jack mentioned, the

3 response to 9/11. Many of the enhancements to

4 security after 9/11 were imposed as redefining the

5 level of adequate protection.

6 Those decisions were made in the

7 Commission, no conditional guidance came back to the

8 Staff on it. We decided that these were redefining

9 adequate protection for these reasons, and consider

10 that in the future. So, what we found is, the Staff

11 has no better guidance today in 2011 than we had in

12 2001 in how to take a significant event and assess it

13 in terms of our framework in terms of a new

14 requirement based on redefining adequate protection.

15 So, we proposed that the Staff would

16 benefit from such guidance. And, as Jack indicated,

17 we think that the public would better understand why

18 we do what we do, and the industry better understand

19 what to anticipate in response to an event like this,

20 if we had more guidance on how to frame such a

21 decision.

22 MEMBER-AT-LARGE STETKAR: Well, I mean,

23 even that anecdote about here we are in -- you know,

the 10th 24 anniversary this weekend, and the Staff yet

25 has guidance, which is something that prompted my
33

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 question about relative timing and priorities

2 regarding this particular recommendation, recognizing

3 the practicality of the time that would be required to

4 actually fully implement it going forward. Anyway,

5 thanks.

6 MR. GROBE: Recommendation 2. Okay.

7 Recommendation 2 addresses seismic and flooding

8 analysis. The Task Force looked at the various

9 external events and identified flooding and seismic as

10 particular areas that we recommend that the Staff

11 focus on.

12 This is because the fundamental knowledge

13 on these concepts, or the data that we have to think

14 about these concepts, or the analytical tools have

15 advanced sufficiently since the `60s and `70s when our

16 current operating fleet was originally licensed, that

17 these issues should be revisited.

18 We had -- let me finish my sentence. Good

19 grief.

20 (Laughter.)

21 MR. GROBE: We had several recommendations

22 in this area. One is longer-term, one is an interim

23 action, and then a rulemaking to make this a lasting

24 recurring activity. 

25 MEMBER-AT-LARGE STETKAR: Okay. Suppose
34

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 the Fukushima event had involved the worst tornado

2 that had ever occurred in the history of the earth,

3 would Recommendation 2 still say update seismic and

4 flooding analyses because these are the areas -- 

5 MR. GROBE: Yes.

6 MEMBER-AT-LARGE STETKAR: -- that we have

7 -- we recognize were one of the most -- 

8 MR. GROBE: And if you're a marketing

9 manager, you appreciate that this is difficult to

10 sell. But, in fact, we actually looked at everything.

11 We did. We talked to each of the experts in each of

12 these areas, and the conclusion was the way the Agency

13 handled winds, high winds, whether it's tornados, or

14 hurricanes, the way it handled ice and snow, there

15 hasn't been a lot of advancement which would cause us

16 to call into question whether or not there's still

17 sufficient basis -- 

18 MEMBER SHACK: Tornado winds are

19 decreasing.

20 MR. GROBE: So, we actually looked at each

21 of these and concluded that seismic and flooding were

22 the two areas that we should focus on, the Staff

23 should focus on.

24 MEMBER POWERS: Looking at your report, I

25 came away saying, Jack, I need a little more
35

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 background context, what you were thinking about on

2 this particular one. In particular, on updating the

3 seismic, how does this interface with GSI-199. And on

4 the flooding analysis, I said this is an area that I

5 have a dint of an ill-spent youth, I'm sure, had to

6 deal with a lot in connection with early site permits

7 and things like that, and the context of climate

8 change. Because what -- I mean, what we do on the

9 flooding analysis, typically, is they look at 50-year

10 or 100-year data, and they say well, what was the

11 worst flood we ever had, and we'll protect against

12 that one. And it's a practicality. There's no data

13 prior to 100 years for many, many of the plants, and

14 even the data you have there's ahhh -- because you

15 don't have to go back very far and people just didn't

16 measure things.

17 So, that context was kind of missing for

18 me on what your thinking was. I'm not criticizing the

19 recommendation.

20 MR. GROBE: I mean, you guys have four

21 questions in one question.

22 MEMBER POWERS: Yes, I did, but I'm really

23 only asking for the context of your thinking about

24 this recommendation.

25 MR. GROBE: Well, I mean, we've been
36

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 recently dealing with concepts of likelihood of dam

2 failure, and consequences of dam failure at a site.

3 And as I'm -- a novice in every technical area. I'm

4 not an expert in any. But as we got into this issue,

5 it became very clear to me that the analytical tools

6 we have today to project the likelihood of

7 consequences of a dam failure are far superior to what

8 we had when we originally licensed these plants. The

9 water flow, the levels, the rapidity with which the

10 water gets to different places just simply are

11 geosynchronous satellites in our ability to map the

12 earth to be able to project that, far superior to what

13 we had 40 years ago.

14 So, it was these two areas where based on

15 our study of what we've done in the past, and

16 extensive discussions with the experts in all of the

17 external events areas, that we concluded warranted

18 revisiting.

19 With respect to 199, let me -- I think was

20 your other question. There is a very close

21 connectivity. 199 addresses the increased likelihood

22 of seismic exceedances east of the Rocky Mountains.

23 Those increased likelihoods, principally, are at the

24 high frequencies which are typically less damaging to

25 structures and large facilities; notwithstanding,
37

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 there is some likelihood that those safe shutdown

2 earthquakes in the current licensing basis could be

3 exceeded, and that should be studied.

4 We evaluated that and concluded that we

5 didn't see a need for imminent action, but we needed

6 -- we saw a need to take some action, and that's 199.

7 The way in which you establish the

8 spectrum in new reactor licensing and in 199 is the

9 same, the ground motion response spectrum. The way in

10 which you design the plant for a new reactor license

11 is that you will design it to meet that spectrum. So,

12 the back end of 199 is different. 199 has you do a

13 probabilistic analysis, either a seismic margins

14 analysis, or a seismic PRA. And if you find

15 exceedances of 10 to the minus 5, then 199 asks you to

16 address those, and identify what would reduce it to

17 below 10 to the minus 5 core damage frequency.

18 So, the back end of 199 is different than

19 the back end of the new reactor licensing concepts. As

20 a matter of fact, the design certs are based on a

21 seismic spectrum that is anchored as .3g. And the

22 design cert is done based on that. Typically,

23 licensees only select sites where that .3g spectrum

24 bounds a specific site ground response, ground motion

25 response spectrum. Otherwise, there's a whole lot of
38

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 analytical work that needs to be done to either show

2 you have margin or redesign the specific parts of the

3 plant. So, typically, licensees will select sites that

4 are bounded by that .3g spectrum.

5 MEMBER SIEBER: Do you foresee that new or

6 advanced studies is seismic, flooding, tsunamis, and

7 other natural effects will affect the licensing basis

8 for existing plants?

9 MR. DORMAN: What we recommended was what

10 we termed the confirmation of the licensing basis,

11 design basis on a 10-year interval anticipating that

12 there will be advances in understanding, continue to

13 be advances in understanding of seismic and flood

14 hazards. And the confirmation -- 

15 MEMBER SIEBER: And new events.

16 MR. DORMAN: Yes. And the reason we use

17 the term "confirmation," if you look at 2.1

18 Recommendation was to do an analysis now of the

19 existing fleet. We used the term, I think, analysis

20 for 2.1. In 2.2 we recommended a confirmation. So,

21 the confirmation in our mind was look at what the

22 change is in the state of knowledge and the state-of23 the-art in analysis and if there are significant

24 changes then you may need to do a re-analysis. But

25 that's why we used the confirmation of the design
39

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 basis, so if there are significant changes over that

2 10-year interval, then that may kick you into an

3 analysis. But we were envisioning a lighter level of

4 effort for the first step in that 10-year -- 

5 MEMBER SIEBER: Well, the term

6 "confirmation," to me, you know, I can take it as a

7 knowledgeable person on this Committee working with

8 the Staff, or I could take it as a public individual

9 who would say I'm going to confirm this, which means

10 I'm going to do my level best to make sure it comes

11 out the same as it was before. And, to me, the term

12 is not exactly the right term to use.

13 MR. DORMAN: Okay.

14 MEMBER SIEBER: I think you ought to

15 approach that with an open mind because as events

16 occur, you may redefine the envelope of the severity

17 of those events, and it may affect the licensing basis

18 of existing plants, and you've got to do something

19 about that.

20 MR. GROBE: There's been a lot of

21 discussion. We have a very robust operating experience

22 program, and if we -- and generic issues program. And

23 if we identified some new knowledge either based on

24 events or research that caused us to conclude that

25 there was a prompt safety concern, we wouldn't wait
40

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 for the 10 years. We would process that promptly

2 through our existing processes.

3 This particular recommendation, it's 2.2

4 I think. It's really unclear. We have to spend a lot

5 of time thinking about the guidance on when we have to

6 redo the analysis, and when it's simply sufficient,

7 and how you make those judgments. And it's this whole

8 concept of confirmation.

9 MEMBER CORRADINI: Is the time frame also

10 part of that hard thinking? I was trying to

11 understand where you guys got the 10 years from. Is

12 this just an example of some sort of periodic

13 reassessment? Is that really the 10 years at this

14 point?

15 MS. CUBBAGE: There's also a recognition of

16 the time it would take to do a reassessment.

17 MEMBER CORRADINI: Okay.

18 MS. CUBBAGE: And you don't want to do it

19 every two years.

20 MR. DORMAN: Yes, you want sufficient

21 interval to allow the evolution of the knowledge and

22 the technology, so you didn't want to do it so

23 frequently that it became -- that you didn't get

24 meaningful evolution in that time period.

25 MEMBER SHACK: So, it was easier to pick a
41

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 time than it was to come up with the criteria for what

2 we -- 

3 MR. DORMAN: That's -- 

4 MR. GROBE: And the timing -- I mean, the

5 licensed life of the existing plants is 40 years. The

6 current license extension is 20 years, and maybe life

7 beyond 60 will be 10 years, don't know where that's

8 going to take us. But it seemed like an appropriate

9 interval.

10 MS. CUBBAGE: And keep in mind that this

11 was a proposal for a rulemaking so there will be a lot

12 of detailed engagement with all stakeholders.

13 MR. GROBE: And you may have the

14 opportunity to engage.

15 MEMBER SHACK: Well, it's 2.1 that -- just

16 come back to that one for a second, because that's an

17 order. And my understanding is that that's a change

18 in the design -- I mean, I look at 199 as kind of a

19 risk-informed approach to this. You're going to go off

20 and look at this, and okay, if you exceed the design

21 basis but you're still okay from a PRA or a seismic

22 margins event, you're okay.

23 You have introduced a new step here now.

24 You're going to actually look at the design basis --

25 and I just want to check that that is, in fact, your
42

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 intent.

2 MS. CUBBAGE: That was the intent.

3 MR. GROBE: That was the intention.

4 MEMBER SHACK: And why choose that over the

5 risk-informed approach that I associate with 199, I

6 guess is my question.

7 MR. GROBE: I can only speak as one Task

8 Force member, but from my perspective it was a re9 baselining. It was -- there's sufficient change in

10 these concepts that we felt -- I felt that there was

11 a need to re-baseline the design basis in these two

12 areas.

13 MEMBER CORRADINI: The re-baselining could

14 mean a new SSE.

15 MR. GROBE: Yes. It will like change SSE

16 at a number of plants.

17 MS. CUBBAGE: Some sites the hazards may

18 have gone down.

19 MR. GROBE: Yes, there are sites where it

20 has gone down.

21 MEMBER SHACK: Did you think through what

22 would happen -- you know, I can envision somebody

23 coming up with a new SSE. I can change equipment, I

24 can read the analyses. It's calling for me to redesign

25 my basemat. And I assume that you will have some sort
43

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 of an -- would there be an exemption at that point?

2 You would go to something like a seismic margin

3 analysis, seismic PRA. You would go to the design

4 basis first before you went to -- which is the

5 difference between 199 -- 

6 MS. CUBBAGE: You're raising some great

7 issues, and I think it's premature for us to get into

8 the details of how that would play out, because we've

9 got -- the Commission has got to weigh in, et cetera,

10 et cetera. And there'll be a lot of dialogue, I

11 believe, going forward on it.

12 MR. DORMAN: But, I mean, you're touching

13 on an issue that I think will be -- not to presuppose

14 what the Commission will direct in terms of what

15 process, regulatory process we'll go through. We said

16 order. But I think that whatever regulatory process

17 we're in, there's going to need to be a robust

18 discussion of what the criteria -- what the Staff's

19 acceptance criteria will be for what we've -- I think

20 our words were something like upgrade equipment, as

21 necessary, or as appropriate. 

22 The acceptance criteria associated with

23 that, because you're dead on. I mean, we can stiffen

24 relays, and we can stiffen pumps, but we're not going

25 to fundamentally change the buildings as a result of
44

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 this re-analysis. So, whether that shows up as an

2 exception to an order, an exception to a regulation --

3

4 (Simultaneous speech.)

5 MEMBER RAY: The draft Generic Letter

6 refers to backfit three different times, the Backfit

7 rule is applied. I took that to mean what it says.

8 MR. GROBE: Recognizing that backfit has

9 four components.

10 MEMBER RAY: Yes.

11 MR. GROBE: Right.

12 MEMBER RAY: But, I mean, I think you're

13 going beyond it just being quite as vague as you were

14 saying. It very specifically says this would then be

15 subject to the Backfit Rule if any change was

16 considered necessary.

17 MS. CUBBAGE: Well, I think -- 

18 MR. GROBE: Actually, that's not what this

19 says. The recommendation -- 

20 (Simultaneous speech.)

21 MR. DORMAN: Generic Letter for 199.

22 MR. GROBE: That's right.

23 MS. CUBBAGE: There's the Task Force

24 recommendation as it stands, because the report is

25 done. Then there's the draft Generic Letter, which is
45

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 on the table. And then there's what's going to go

2 forward to the Commission, and what the Commission

3 will decide, that may or may not change the direction

4 of GI 199, but there -- 

5 MEMBER RAY: Well, the Generic Letter is

6 broader than GI 199. It includes it, but it also

7 includes the west coast plants.

8 MR. GROBE: It does, and that was -- 

9 MEMBER RAY: And, like I said, I took it

10 because of the timing to reflect an evolution of the

11 next step of what you were just talking about. I

12 realize you're not the author of the Generic Letter,

13 but the Generic Letter does reflect, I thought, what

14 these Task Force recommendations were saying.

15 MS. CUBBAGE: There's a parallel, but I

16 wouldn't necessarily draw the -- 

17 MEMBER RAY: The two things may be

18 disconnected.

19 MEMBER SIEBER: But they should mesh, so we

20 should -- 

21 MS. CUBBAGE: Eventually -- 

22 MEMBER SHACK: But just coming back to

23 your's, to me, this is part of your Recommendation 1.

24 Right? When you said order and changing the design

25 basis, you had, in fact, a notion of a redefinition of
46

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 adequate protection.

2 MR. GROBE: Yes, absolutely. And it would

3 replace that 199.

4 MEMBER SHACK: That is what happens with

5 the Backfit Rule in this particular case. That's at

6 least your vision -- 

7 MR. GROBE: That's one path through the

8 Backfit Rule analysis, yes.

9 VICE CHAIRMAN ARMIJO: Jack, I'd like to go

10 back to something that John brought up. The

11 recommendation seems very narrow to me that it's

12 seismic and flooding. That's what happened at

13 Fukushima, obviously that should be in there. That's

14 the way it comes across, but there's other severe

15 natural phenomena of long duration other than

16 earthquakes and tsunamis. And John mentioned

17 tornados. I've experienced hurricanes, but there's

18 also blizzards, long duration, isolation of a plant.

19 Could damage access and power in a way

20 that's different from a flood. And you've kind of

21 mentioned that yes, we covered that with this

22 recommendation. I just want to make sure that that is,

23 in fact, true.

24 MR. GROBE: That's our opinion, and that's

25 the underpinning of the recommendation. Seismic and
47

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 flooding is not here because that's what happened at

2 Fukushima. It's here because those are the areas that

3 we think we need to advance in the way in which we

4 regulate our operating plants.

5 MR. DORMAN: Because there's a significant

6 evolution of knowledge and state-of-the-art since

7 these plants were licensed. When we looked at high

8 winds and snows, and freezing, and other issues from

9 external hazards, we didn't see that kind of

10 significant delta in where we are -- where the state11 of-the-art is today from where the plants were

12 licensed. So, that's why those didn't show up in

13 there. And we perhaps could have benefitted by a

14 little bit more discussion in the report of why we

15 left some things out, but if we started getting into

16 a discussion of all the things we didn't include, the

17 report would have been a lot longer. But that was the

18 thinking.

19 VICE CHAIRMAN ARMIJO: Thank you.

20 MEMBER-AT-LARGE STETKAR: Dan or Jack, I

21 want to come back to this notion of 10-year

22 reconfirmation, if you want to characterize it that.

23 First of all, the 10 years is an arbitrary. There are

24 many, many international regulatory bodies that

25 invoked a licensing framework that involves a 10-year
48

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 periodic safety review. That's fairly standard in a

2 large part of the world.

3 MEMBER POWERS: Also completely arbitrary.

4 MEMBER-AT-LARGE STETKAR: Well, but

5 consistent -- we get points for consistency.

6 MR. GROBE: Our 10 years is not arbitrary.

7 MEMBER-AT-LARGE STETKAR: The question in

8 seriousness is why restrict that 10-year periodic

9 examination, if you want to call it that, to seismic

10 and flooding? You know, you mentioned well, we haven't

11 really learned much about fires in the last four

12 years. I would challenge that substantially.

13 I think we've learned a heck of a lot

14 about fires in the last decade, compared to where we

15 were in the late 1990s. We've done an awful lot of

16 research work, experimentation that has changed our

17 notion about the behavior of fires. We've gathered

18 data that has changed our notions about the frequency

19 of various types of fires, the consequential damage

20 from fires. So, it's not clear to me why fires

21 shouldn't be included in that notion.

22 We've learned an awful lot about how pumps

23 behave under near-cavitation conditions. We've

24 learned an awful lot about what cavitation might be.

25 We've learned an awful lot about what margins might
49

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 exist for net positive suction head conditions in

2 various types of designs over the last decade compared

3 to 40 years ago. Why shouldn't those issue and the

4 fundamental design basis credit for adequate net

5 positive suction head also be reviewed on a 10-year

6 basis?

7 All of those issues are folded into a

8 regular periodic safety review. Many of them, it's

9 easy to look at the last decade and say well, we

10 really haven't learned very much. Others, you do

11 learn. So, it's not clear to me why simply seismic

12 and flooding.

13 MR. GROBE: There's not a scientific answer

14 to th is question.

15 MEMBER-AT-LARGE STETKAR: Okay.

16 MR. GROBE: The -- we had debates, why not

17 other natural events? And then you get why not other

18 things that are not natural events, and why not do a

19 periodic safety review? And we provided a very

20 comprehensive articulation of our regulatory processes

21 as contrasted with the others around the world, and

22 provided that to the IRS team and they acknowledged

23 that our regulatory structure is equivalent to what --

24 the robustness of our operating experience, our

25 generic issues, our revisiting of issues on a realtime
50

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 basis, but it's equivalent.

2 This was simply a recognition -- this

3 particular recommendation was a recognition of the

4 advancements in these areas and appreciation that

5 those advancements may continue. And it's a judgment.

6 There's nothing scientific about this.

7 MEMBER-AT-LARGE STETKAR: The problem is

8 that historically a lot of our revisiting of issues

9 based on operating experience has been a reactionary

10 process, something has happened in the industry. We

11 have a station blackout, so station blackout becomes

12 important. Reactor trip breaks fail to open, so ATWS

13 becomes important. That's a different notion that

14 sort of stepping back every decade or so and asking

15 yourself what have we learned, and what does that

16 knowledge tell us looking forward.

17 MR. GROBE: Yes, I'd like to just expand

18 that a little bit. It's not just response to events,

19 for example, the hardened events was from PRA. And

20 there's other things that we've learned from PRA. And

21 need to continue doing that. And our view, as

22 contrasted with others in other parts of the world is

23 that we should do that on a realtime basis, and not

24 wait every 10 years to do it. 

25 This particular recommendation was simply
51

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 a continuation of the concept of why we're ordering

2 this re-analysis. It's because the state of knowledge

3 has changed so dramatically, maybe it won't change in

4 the future. It's possible that we know all that we're

5 going to know. Of course, we never know all that

6 we're going to know, but what changes is not

7 significant, in which case a re-analysis is not

8 necessary. It's not a satisfying answer. I apologize.

9 CHAIRMAN ABDEL-KHALIK: Okay. Let me just

10 point out that we are on Recommendation 3, and we have

11 already been -- 

12 (Simultaneous speech.)

13 MR. GROBE: Recommendation 3 is a bit

14 easier to deal with. There have been situations where

15 seismic events have caused fires. It's a very common

16 thing in industrial, or in residential, and urban

17 situations. It also occurred at the KK earthquake in

18 Japan a number of years ago, where they had a fairly

19 significant transformer fire as a result of the

20 earthquake.

21 This needs to be studied. We couldn't

22 come up with a specific recommendation on how you

23 would modify, how you would apply seismicity

24 protection to fire, weather systems and things of that

25 nature. This was a longer-term focus area, not
52

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 meaning to take 10 years to do it, but just take the

2 appropriate amount of time. And we couldn't provide

3 a specific recommendation.

4 Recommendation 4, station blackout. Gosh,

5 one, two, three, four, five, six, seven words. A huge

6 topic. It's clear the Station Blackout Rule that we

7 currently have is predicated on the concept of some

8 event removes electrical power from offsite, and

9 reliability results in loss of electrical power

10 onsite. And that's the foundation for the regulations

11 that we currently have.

12 The Task Force visited that in light of

13 what occurred at Fukushima, and the concept of cliff

14 edge events, and clearly station blackout is a cliff

15 edge event if it occurs. And it should be protected

16 more holistically in the opinion of the Task Force

17 than what our current regulations provide.

18 And we conceptualized a three-phase

19 protective scenario with eight hours of protection,

20 what we call coping, with minimal operator action,

21 recognizing that during those eight hours the operator

22 should be focused on recovering electrical power and

23 preparing for a longer-term station blackout, if it's

24 necessary, but not manipulating lots of equipment;

25 that that should be given to the operators to do the
53

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 operating job of dealing with the casualty.

2 An extended period of coping of 72 hours,

3 the point of that coping period is to give enough time

4 to essentially have the calvary arrive to receive

5 support from offsite, and that's a not normal operator

6 action, beyond normal operator action to establish

7 that 72-hour coping period, but still equipment that's

8 available on site. And then offsite equipment that

9 would be made available to the facilities in the event

10 of a station blackout exceeding 72 hours.

11 So, it's a three-phase concept. It also

12 includes protections beyond the design basis

13 protections. For example, in the proposal the concept

14 is that you provide this 8-hour coping in such a way

15 that it's protected from at least one elevation in the

16 plant beyond the projected flood levels, so it's

17 conceptualized to be protected beyond design basis

18 events at some level.

19 CHAIRMAN ABDEL-KHALIK: What is the logic

20 for selecting eight hours and 72 hours?

21 MR. GROBE: The logic for eight hours was

22 simply to give the operators enough breathing space to

23 respond to the casualty, and if it appears that

24 they're not going to be able to respond to the

25 casualty successfully, to have sufficient time to put
54

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 in place the equipment that would get you for a longer

2 period of coping. And this is equipment that would not

3 necessarily be installed in the plant.

4 MEMBER CORRADINI: So, can I ask a question

5 here, because I understand you had to pick some time,

6 and that makes some sense to me. But at least as I

7 read the information from the event in Japan, for

8 Units 2 and 3, they were successful in having RICSI

9 and HIPSI run for two to three days.

10 MR. GROBE: Don't know how they did that.

11 I'm very interested in that. That's true.

12 MEMBER CORRADINI: Okay. So, I'm struggling

13 with what -- I mean, I don't want to lessen -- because

14 I do agree with the recommendation, but on the other

15 hand, there is a fatal -- there is a flaw in the

16 design base that caused the event. So, if you go

17 through Recommendation 2 where you've now very

18 diligently relooked at the design base, maybe even re19 baselined what the design base is relative to seismic

20 and flood, what I see here is almost an assumption

21 that somehow you've missed the design base, now you've

22 gone beyond design base, and now from a defense-in23 depth standpoint this is what you're requiring.

24 That's my only justification for understanding why you

25 came to this. Am I off base?
55

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. GROBE: You're exactly within the

2 regulatory framework in Recommendation 1.

3 MEMBER CORRADINI: Okay, fine.

4 CHAIRMAN ABDEL-KHALIK: Would you agree

5 that the selection of -- for specifying eight hours

6 and 72 hours may not be optimal for all sites?

7 MR. DORMAN: Yes. I think, ultimately, the

8 question is-- we put out eight and 72 hours to frame

9 the strategies that we were talking about. And in our

10 discussions, those were reasonable times to enable the

11 operators to get the 72 -- get the extended coping in

12 place, and then get the offsite equipment. But I

13 think it depends on how much action needs to be taken

14 to get the extended coping in place. It's potential

15 that you might need more than eight hours to get the

16 extended coping in place. It may -- it's possible that

17 you can show that under conditions associated with a

18 station blackout and the initiating event that caused

19 you to be in a prolonged station blackout, that you

20 can demonstrate that you can with confidence get that

21 extended coping in place in four hours, then maybe you

22 could justify a four hours.

23 Similarly, if the offsite equipment is

24 near enough and you have confidence in infrastructure

25 to get it to the site and connect it, you might
56

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 justify something less than 72 hours. If you go for

2 something more regional, you may need to go longer

3 than 72 hours.

4 So, yes, I think there's room for

5 discussion in the rulemaking process of a performance

6 basis for those things. I think there's an elegance

7 to having one set of answers. We noted that we're

8 kind of several different answers across the fleet

9 today in terms of four hours, or eight hours, or

10 alternate AC. But, ultimately, the best thing for a

11 site is the best thing for a site, so I think there's

12 room for discussion of performance basis -- 

13 MR. GROBE: You're going to get a little

14 taste of what it was like in the cave for four months.

15 And Amy and Nathan just sat there when Gary, and Dan,

16 and I would get into it, and they just kind of sat

17 back and said oh, man. But I wouldn't answer that

18 question the same way Dan did.

19 Eight hours, in my opinion, is a minimum.

20 You're talking about an operator that is having to

21 deal with a casualty. It's very significant. It's

22 clearly beyond anything we've analyzed and

23 contemplated, because we changed the design basis. 

24 This is a situation where the operator is

25 having to deal with something that he does not
57

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 understand, possibly, and is not -- his plant has not

2 been designed to deal with this in a normal way.

3 The operator is going to have to deal with

4 two things, trying to figure out why he's lost offsite

5 power and onsite power, and what he needs to do to

6 deal with this. And it might be at 1:00 in the

7 morning where he doesn't have a whole maintenance

8 staff, and a whole electrical staff, and engineering

9 staff to help him or her, and then deal with the

10 concept of hey, I might not get it done in eight

11 hours, and we've got to start getting ready for beyond

12 eight hours.

13 That's a lot of stuff. In HRA analysis

14 perspective, you're putting the operators in a

15 difficult situation. So, I would not go below eight

16 hours, personally; 72 is debatable, 72 is simply based

17 on making sure there's ample margin to get stuff from

18 offsite. But the eight, in my mind, is a fairly firm

19 concept just from the standpoint of looking at what

20 operators have to do in the control room in a casualty

21 situation that they don't understand.

22 MEMBER SIEBER: Actually, the use of eight

23 and 72 is sort of deterministic in nature, and I

24 suspect that each plant has its own unique

25 circumstances. And we ought to have sufficient
58

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 flexibility to accommodate the circumstances that

2 exist, and provide sufficient margin because not

3 everything happens the way you would like it to.

4 MR. GROBE: Yes.

5 MEMBER SIEBER: So, rather than nail down

6 specifically what these times ought to be, and have a

7 licensee say I meet the time, but I can't perform the

8 function under his breath, I would prefer a more open

9 mind toward what the baseline should be. And a risk10 basis time line serves us better than deterministic

11 times.

12 MEMBER-AT-LARGE STETKAR: Jack, the Task

13 Force spent, obviously, a lot of time on this issue.

14 And I need to ask you a question so that I can

15 understand the thought process.

16 In the Task Force deliberations, what is

17 a station blackout? I mean, let me ask you two

18 questions so you can give me a yes or no answer. Is

19 a station blackout the complete absence of any

20 alternating current power whatsoever? Yes or no? No

21 alternating current.

22 MR. GROBE: I believe the answer is yes.

23 MEMBER-AT-LARGE STETKAR: Okay.

24 MR. DORMAN: Yes, I think that fits how we

25 applied it, which is -- 
59

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER-AT-LARGE STETKAR: Okay. Let me ask

2 you the second question, because I was hoping that

3 that would be yes.

4 Is a station blackout a situation where my

5 only source of alternating current is from an

6 operating, perhaps non-safety, perhaps manually

7 started generator that I've connected to the plant so

8 I have alternating current lighting my lights and

9 powering some minimal equipment. Is that a station

10 blackout? Yes or no? Because I need to understand

11 this distinction.

12 MS. CUBBAGE: In our minds, that type of

13 equipment would only come into play after the initial

14 eight-hour period.

15 MEMBER-AT-LARGE STETKAR: So, a station

16 blackout is no alternating current in this notion.

17 The eight-hours is to cope with no alternating

18 current.

19 MR. DORMAN: Yes.

20 MEMBER-AT-LARGE STETKAR: Thanks. I'm --

21 honestly, you know, yes or no was fine. And I didn't

22 hear a lot of -- 

23 MEMBER POWERS: I really honestly think you

24 don't want that answer. I think you want to say lack

25 of adequate alternating power.
60

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. DORMAN: Yes. I think what's different

2 from -- what's different at Fukushima from what's

3 envisioned in the station blackout reg guide is it's

4 not just the power source from offsite and the power

5 source from onsite, but all of the switch gear was

6 flooded out, as well. So, my it depends on your

7 answer is, where is that generator hooking into? If

8 it's hooking into that same switch gear it's not doing

9 any -- 

10 MEMBER-AT-LARGE STETKAR: In some sense it

11 doesn't. I'm interested in the fundamental concept of

12 the thing that we call a station blackout, because

13 that concept has been twisted in a regulatory and an

14 application framework with many, many different

15 interpretations to the point where people say well,

16 I'm coping with a station blackout, but I have

17 alternating current power available, but that's part

18 of what I call a station blackout. So, I was

19 fundamentally interested because you do have

20 recommendations that are explicit, regardless of

21 whether it's eight hours or some arbitrary time of

22 coping with a particular condition in the plant. And

23 that's what I was trying to understand. Thanks.

24 MR. GROBE: There is an interim

25 recommendation that goes along with the rulemaking,
61

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 and that is to -- we do have this B5b equipment in our

2 plants -- 

3 MEMBER BROWN: Can I ask one question

4 relative to his thought? Talk about no AC power,

5 John, I presume you mean also any batteries that they

6 -- 

7 (Simultaneous speech.)

8 MEMBER-AT-LARGE STETKAR: No, I'm -- things

9 that spin around and create -- 

10 MEMBER BROWN: Well, that's why I asked the

11 question. AC power relative to batteries would be --

12 if you develop for eight hours, or six hours, or two

13 hours, is not within the I've lost all AC power. It's

14 available. Okay. I wanted to make sure I understood

15 that context.

16 CHAIRMAN ABDEL-KHALIK: Please continue.

17 MR. GROBE: Let's move on to Recommendation

18 5. Recommendation 5 has to do with reliable hardened

19 vents. The word "reliable" is clearly undefined. At

20 least we've all defined it in our own minds, but

21 there's no consensus, necessarily, on what reliable

22 means.

23 I think I addressed this briefly earlier.

24 In our minds, reliable embodies the concepts of

25 passive action versus active action. It involves the
62

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 concepts of availability without AC power, the concept

2 of accessibility to the equipment that needs to be

3 operated in different scenarios. So, embodied also in

4 this recommendation is to study other containment

5 designs and identify whether or not there's a need for

6 any change in other containment designs.

7 MEMBER SIEBER: Is the Staff taking any

8 steps to fully determine what caused the hydrogen

9 explosion at Fukushima, so that there are Lessons

10 Learned, because they supposedly had hardened vents

11 even though they had more than one unit connected to

12 a single vent. It resulted in destruction of three

13 reactor buildings, and potentially a containment pool,

14 four reactor buildings.

15 MR. GROBE: There's a number of things that

16 are going on. The industry has a Task Force that's

17 working on developing a sequence of events. The

18 Government of Japan has directed the completion of a

19 detailed study of the events and developing a sequence

20 of events. Department of Energy is going detailed

21 study of the core progression -- the accident

22 progression and utilizing our severe accident modeling

23 to, essentially, benchmark models. So, there's a

24 number of things going on.

25 Actually, Recommendation 6 is hydrogen
63

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 control. The difficulty the Task Force had was that

2 there wasn't sufficient information. The common

3 belief at this point in time was that the containment

4 vessel was pressurized to a point where gases escaped

5 through the seals, the O rings on the head, that there

6 was elastic deformation of the bolts at the head, and

7 that allowed gases to exceed, which allowed hydrogen

8 to get into the reactor building, and the common

9 speculation at this point is that there was -- and

10 there's some data to support this, that there was

11 crossflow between Units 3 and 4, but that's not yet

12 confirmed. And we expect that that will be something

13 that we understand better in the future, and that

14 forms the basis for this long-term recommendation.

15 MEMBER SIEBER: So, work is going on, and

16 it appears as though you understand all the

17 intricacies, so I'm satisfied.

18 MR. GROBE: Right.

19 MEMBER SIEBER: Thank you. 

20 MR. GROBE: Recommendation 7 has to do with

21 instrumentation, electrical power for instrumentation

22 for the spent fuel pool, electrical power for spent

23 fuel pool makeup, as well as an independent capacity

24 to provide spray into the spent fuel pool in the event

25 of a severe beyond design basis accident.
64

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 VICE CHAIRMAN ARMIJO: That instrumentation

2 problem with the spent fuel pool, there were

3 instrumentation problems related to the vessel and the

4 core. I wonder why your recommendation was limited to

5 the spent fuel pool, when the real problem was in the

6 core.

7 MR. DORMAN: I think we touch on

8 instrumentation in the station blackout recommendation

9 in terms of the instrumentation available to the

10 operators relative to the reactor during a station

11 blackout.

12 Here we were focused on the recognition

13 that the problem was not in the spent fuel pool, but

14 absent information about the spent fuel pool, the

15 operator spent tremendous of energy addressing a

16 potential problem in the fuel pool, that if they'd had

17 adequate instrumentation they may have been able to

18 focus more of their energy on the reactor. So, I

19 think the answer for instrumentation for the reactor

20 is in our station blackout recommendations of what

21 instrumentation which should be available under those

22 conditions.

23 MEMBER REMPE: That's not consistent with

24 what I've read. For example, the thermocouples that

25 they use were Type T thermocouples. They had
65

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 temperatures of 500 degrees C for some of the units or

2 higher, so power, or low power is not just the only

3 issue, there's also an issue that since this protects

4 beyond the maximum operating temperature, the water

5 level was needed to make some near-term actions, so I

6 guess I would be more concerned about the adequacy of

7 the actual sensors, not just the need for power of the

8 sensors.

9 MS. CUBBAGE: I think that's the type of

10 area where as more information becomes available, it

11 could form future recommendations as part of the NRC's

12 long-term. But as far as our 90-day review that wasn't

13 a level of detail we were able to get into.

14 MR. GROBE: Yes. It clearly was beyond our

15 capacity in 90 days to deal with this issue. We could

16 have had a longer-term recommendation to look at it,

17 because it was a challenge, and it's becoming more

18 clear as we understand the condition of the reactors

19 and the cores that the instrumentation was

20 significantly challenged.

21 MEMBER POWERS: Without being too critical

22 of the recommendation, I just have to point out that

23 I have now been through three severe accidents, and

24 every one of them people come back and said gee, we

25 need more instrumentation. And I think one of the
66

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 problems you run into is that whatever instrumentation

2 you put in would probably be inadequate for the next

3 severe accident, because it will be different.

4 I think the recommendation is fine, but I

5 caution you that if we rely on additional

6 instrumentation you get into two problems. One, any

7 additional instrumentation is a distraction to the

8 operator, at some point it's a distraction. And

9 second of all, it probably will not help on the next

10 accident. Every accident is just different.

11 CHAIRMAN ABDEL-KHALIK: Well, that doesn't

12 mean that you don't sort of take actions to correct

13 events of similar nature.

14 MR. GROBE: There's a unique absence of

15 information regarding the spent fuel pool beyond

16 normal conditions. And this was intended to address

17 that.

18 MEMBER POWERS: Well, I mean, the problem

19 is it's almost a regulatory problem. The regulation

20 is don't let the water pool drop below a certain

21 level, so the instrumentation is designed to make sure

22 it doesn't drop below that. One it drops below that

23 level, you've got nothing -- there's no help.

24 MR. GROBE: Okay. Recommendation 8 has to

25 do with three sets of documents that were developed at
67

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 different times. The emergency operating procedures

2 are actually procedures that are step-wise, and

3 they're expected to be implemented. The severe

4 accident management guidelines are not procedures.

5 They're guidelines for things you might think about

6 doing if you get beyond your capacity in your

7 emergency operating procedures. And the EDMGs, the

8 Extensive Damage Mitigation Guidelines are

9 specifically tailored to a loss of large areas of the

10 plant due to fire and explosion. 

11 As I said, these documents were developed

12 over a period of time, different periods of time, and

13 what we found is that EOPs are required, EDMGs are

14 required, SAMGs are not required. The things on

15 implementation, you will likely go through them. At

16 least, certainly, there's a relationship between them

17 that is not necessarily recognized in how we develop

18 the procedures. Command and Control training

19 exercises was not as robust as it could be, so the

20 recommendation here is that we focus some attention on

21 the relationship between these procedures, make

22 changes, as necessary, to make that relationship

23 seamless, address Command and Control issues as you

24 transition into these different regimens, and then

25 address appropriate training and exercises once this
68

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 activity is completed.

2 CHAIRMAN ABDEL-KHALIK: Now, the industry

at the August 31st 3 meeting expressed concern about the

4 level of training that is implied in this for

5 operators with regard to SAMGs and EDMGs, and the

6 point that was made was that we should, essentially,

7 focus the training of the operators on things that we

8 expect them to do; meaning that training with regard

9 to SAMGs should only be limited to familiarization.

10 MR. GROBE: And that could be completely

11 appropriate. Once you complete the integration of

12 this to build that framework, and you clearly define

13 the Command and Control structure and how things are

14 going to be done, familiarization training could be

15 sufficient, as long as it's repeated and it -- this is

16 not a definition that all operators have to be

17 actionable as if they were the person that's going to

18 be making the severe accident management decisions in

19 the technical support center. Many of those decisions

20 will be made in the technical support center, and we

21 don't expect operators to be severe accident

22 management experts.

23 CHAIRMAN ABDEL-KHALIK: So, would it be

24 fair to say that the word "integrate" has not been

25 clearly defined at this stage?
69

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. GROBE: Actually, that's recognized in

2 the report, and it specifically references that we

3 need to engage with those people that develop the

4 individual guidelines for each of these documents, get

5 them all in a room and figure out how these procedures

6 would work together.

7 MS. CUBBAGE: And our recommendations with

8 regard to training are specific to those that are

9 expected to implement the strategies and decision

10 makers, not necessarily targeting control room

11 operators. That will have to play out in what level

12 of training -- additional training may be required for

13 operators.

14 MEMBER BLEY: Is the work in this area now

15 that Staff is taking a more deep plan to things like

16 the SAMGs, is the work necessarily being coordinated

17 with industry, and how are we moving forward to kind

18 of make sure we keep the operator's perspective in

19 this, as well as -- 

20 MR. GROBE: The answer is no, the work has

21 not been coordinated with the industry. The Task

22 Force was charged with generating this report -- 

23 MEMBER BLEY: I mean, after your 90-day

24 report.

25 MR. GROBE: I understand the expectation
70

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 from the Commission as well as the expectation from

2 all our stakeholders is that we talk to them. But the

3 Commission has clearly set that expectation. And this

4 is an excellent example of where the Task Force

5 actually recognized that, as well. 

6 These are very complex things. We need to

7 work with the industry and the experts.

8 MEMBER BLEY: And that's not yet begun.

9 MR. GROBE: No.

10 MR. DORMAN: No, the 21-day paper is due to

11 the Commission tomorrow, and then we'll get direction

12 from the Commission. We anticipate that assuming they

13 direct the Staff to move forward on this one, that

14 then we will be reaching out and beginning that

15 engagement.

16 MR. GROBE: Yes, we've had two lengthy

17 public meetings with all of our stakeholders to date;

18 the one the Task Force conducted, the second one was

19 conducted by a group of Office Directors just a few

20 days ago.

21 MEMBER-AT-LARGE STETKAR: You mentioned

22 something and we discussed this a bit at the

23 Subcommittee meeting also. I have to paraphrase what

24 you said, but you said something to the effect that

25 well, we only envision training the operators to the
71

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 extent that they have some notion of the severe

2 accident mitigation guidelines because the real

3 decision makers will be the people in the technical

4 support center.

5 We license operators in this country and

6 around the world to be the people who are legally

7 responsible for operating the nuclear power plant.

8 They are the most informed people on a day-to-day

9 basis for how the plants operate, the function of the

10 equipment, the particular status of the plant. Are

11 you proposing to remove the responsibility for making

12 decisions about managing the progression of events at

13 a plant and put that responsibility in the hands of

14 the technical support center decision makers? And, if

15 so, how are we going to license those people and give

16 them the same knowledge level that the operators have?

17 MR. GROBE: Actually, it's addressed in the

18 recommendations.

19 MS. CUBBAGE: Right. And I think you

20 mischaracterized. If you said that's what we said

21 last time, what we were saying is that is consistent

22 with what's going on today, and we were recommending

23 that -- 

24 MEMBER-AT-LARGE STETKAR: But what I just

25 heard is this notion of well, maybe just limited
72

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 training of the operators so they're familiar with the

2 general concepts is okay because the real technical

3 expertise and the decision makers will be out there in

4 that technical support center. And I believe that's

5 what you just said this morning, unless I'm really

6 misinterpreting what you said.

7 MR. GROBE: I think we all understand this.

8 The -- once you get into a severe accident -- the

9 reason these are guidelines and not procedures is

10 because you can't write a set of procedures that

11 contemplates all potential scenarios. And operators

12 operate per a set of procedures within that construct

13 of a set of procedures.

14 The operators need support. If they get

15 into a severe accident situation that's beyond the

16 scope of training and procedures they have, they can't

17 make decisions in the control room without support.

18 The SAMGs are contemplated to provide a framework for

19 supporting the operators.

20 There may be decisions on strategies that

21 are beyond the capability of the operators to

22 understand because you need to get a bushel basket of

23 Charlie Tinklers and put them in a room and tell me

24 what's going on and what do you recommend, and why?

25 And that's the way this would progress, and
73

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 recommendations would then go from the TSC to the

2 control room. But I cannot imagine us being in a

3 position of training the operators to understand all

4 of that. 

5 It would have to take -- and the focus of

6 this recommendation is we really haven't spent

7 enough time on this question of how the Command and

8 Control structure is defined. And if, in fact, there

9 will be decisions made in the TSC, then those should

10 be licensed people. And we haven't focused on that

11 either, and that's part of the recommendation.

12 MEMBER SIEBER: There is a legal issue.

13 The only one who is authorized to manipulate the

14 reactivity of the reactor is a licensed operator. And

15 if the plant manager is not licensed he can't tell the

16 operator what to do -- 

17 MR. GROBE: That's right.

18 MEMBER SIEBER: -- to manipulate the

19 plant. And at least in the facilities that I have

20 worked in or inspected, that's the way it operates.

21 MR. GROBE: Absolutely. And that's -- 

22 MR. DORMAN: But I think the -- part of

23 what I heard in the industry comment in this regard

24 is, you've got these operators 99.999 percent of their

25 time they're going to be in normal operating
74

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 procedures, abnormal operating procedures, EOPs,

2 that's where we want to focus their training. If we

3 end up doing a whole bunch of training on SAMGs

4 detracting from the things that we expect them to do,

5 then we may be introducing a different kind of risk in

6 human performance, so we want to focus the training on

7 the SAMGs to the people who are doing the different

8 kind of thinking out in another room under those

9 conditions. Have the operators be familiar with what

10 that is, so that when they get the phone call from the

11 TSC it's not total shock, but that ultimately it's the

12 operators who are going to be manipulating the -- 

13 MEMBER SIEBER: That's right.

14 MEMBER-AT-LARGE STETKAR: I know we're

15 short on time, but let me just say that I was an

16 operator and a shift supervisor after Three Mile

17 Island, and the notion that we had in the plant was

18 that people were changing the fundamental bases of how

19 we dealt with certain events. And we were told to

20 don't bother your little heads, really smart people

21 out there who know a lot more than you do are making

22 these decisions, and you just worry about implementing

23 them. I certainly hope we're not getting into that,

24 regardless of what the industry says about training

25 the operators in the control room. I hope we're not
75

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 getting back into that mind set.

2 MEMBER SIEBER: Well, the operators should

3 have sufficient knowledge to know that these exist and

4 how they apply to their plant so that they can take

5 advice from the TSC.

6 (Simultaneous speech.)

7 CHAIRMAN ABDEL-KHALIK: Let me just point

8 out that we have promised NEI 10 minutes to make a

9 presentation; and, therefore, I would appreciate it if

10 you try to conclude your presentation by 20 after the

11 hour.

12 MR. GROBE: Okay. I'll need some assistance

13 on that.

14 (Laughter.)

15 MR. GROBE: Recommendations 9, 10, and 11

16 deal with emergency response, the preparedness aspect

17 of the defense-in depth. Nine are actions that we

18 think should be taken on a short-term, and as you

19 progress through 9, 10, and 11 you get into some

20 research. 

21 Just to give you an idea, part of 9 with

22 respect to ERDS is converting to a -- I'm not going to

23 get this right, a computer-based -- a more

24 sophisticated computer-based communications

25 technology. When you get to 11, it's looking at how
76

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 might we use satellite technology to communicate with

2 the cloud and make that available to everyone. So,

3 that's kind of the progression that you have through

4 9, 10, and 11. And what we're dealing with here is

5 multi-unit events, extended station blackout, and

6 those types of concepts and how you would deal with

7 those.

8 MEMBER SIEBER: Do these recommendations

9 contemplate enhancements to your predictive dose

10 projection tools?

11 MR. GROBE: Yes, that's specifically

12 addressed.

13 MEMBER SIEBER: That needs to -- 

14 MR. GROBE: Recommendation 12 is an

15 internal recommendation. How is that? Who-who.

16 Recommendation 12 focuses on how we train our

17 operators, and how we utilize our reactor oversight

18 process. Excuse me, thank you, our inspectors. How

19 we train our inspectors and how we utilize our reactor

20 oversight process. And unless there's any questions,

21 I don't know that we need to talk much more about

22 that.

23 The next slide is -- 

24 MEMBER POWERS: When you think about more

25 attention to defense-in-depth, does that mean that you
77

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 would go back and revisit the issue of containment

2 over pressure?

3 MR. GROBE: I'm -- 

4 MS. CUBBAGE: The last item is specific to

5 oversight, so allocation of inspection resources and

6 prioritization, and whether that's a risk-informed or

7 a risk-based, and the incorporation of more defense8 in-depth considerations so that there's some attention

9 paid, or more attention paid to beyond design basis

10 features such as SAMGs, hardened vents. I mean, this

11 is really an inspection oversight recommendation.

12 MR. GROBE: You weren't asking a question

13 about the recommendation, were you? You wanted to get

14 into CAP, didn't you?

15 (Simultaneous speech.)

16 MR. GROBE: In the CAP papers that we've

17 provided you, there's -- let's not go there, please.

18 It's -- that's another conversation.

19 MEMBER POWERS: One we'll likely have.

20 (Laughter.)

21 MR. GROBE: Slide 12. This is new, I

22 believe, since the last time we met with you. We got

23 a Commission Staff Requirements Memorandum. We had

24 three -- actually, four actions. The first action was

25 to provide a Commission paper in 18 months on
78

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Recommendation 1. The second action was to provide in

2 five -- I think it was five days the charter for the

3 path forward in studying the Task Force

4 recommendations. That Commission paper is up at the

5 Commission. We don't have a direction on that yet.

6 Second was to prepare -- or third was to prepare a 21-

7 day vote paper on those actions that should be

8 initiated without delay. And I apologize for being a

9 bit late, but we were working on that paper and I lost

10 track of time this morning, so that paper goes up

11 tomorrow and will be available. And then the -- 

12 MEMBER SHACK: This is a preview. Are they

13 different from the recommendations you discussed last

14 week?

15 MR. GROBE: It's a subset, and there are

16 some differences. And this is the -- the Task Force

17 was set up in a odd way, to be quite frank. It was set

18 up differently than task forces in the past, where it

19 reported directly to the Commission. And the

20 Commission decided to put us back in process, and have

21 the Task Force recommendations report to a higher

22 level body within the Staff to make decisions on how

23 the Staff should proceed in recommendations to the

24 Commission in those areas of policy. So, the group of

25 folks which is our Office Directors, essentially, and
79

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Regional Administrators have made some decisions on

2 what should be initiated without delay. And the way

3 in which some of these recommendations are being

4 handled is different than what the Task Force

5 recommended. And that's assuming that the paper

6 doesn't change a whole lot in the next 24 hours, which

7 is always possible.

8 The 45-day paper is really the compendium.

9 It addresses what's in the 21-day paper, but it also

10 addresses all the other recommendations and

11 contemplates things beyond the recommendations with

12 the exception, of course, of Recommendation 1. And it

13 is intended to provide some structure on

14 prioritization, and resources, and things like that.

15 It will not be sufficient -- there will

16 not be sufficient time to provide a tremendous amount

17 of clarity, but there will be a framework for

18 prioritization and resources, and will address the

19 recommendations that are not addressed in the 21-day

20 paper. 

21 CHAIRMAN ABDEL-KHALIK: We were tasked with

22 the evaluation of this 45-day prioritization report,

23 and we hope and expect that you will come back and

24 brief us after that report is prepared so that we will

25 be able to prepare our evaluation of such
80

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 prioritization.

2 MR. GROBE: Let me just -- it will likely

3 not be us.

4 MEMBER CORRADINI: Who's the lead on that?

5 That's maybe what -- 

6 MR. GROBE: That's what I was just going to

7 say. Let me tell you a little bit about the structure

8 that we've set up and recommended to the Commission,

9 and we're expecting an SRM from the Commission that

10 will either approve that or give us different

11 direction.

12 But, essentially, all of the major program

13 office directors and the regional administrators sit

14 on a body that is going to provide oversight. And in

15 the Commission paper it's contemplated in the context

16 of a Steering Committee. It's chaired by Marty

17 Virgilio, the Deputy Executive Director for Reactors.

18 That Steering Committee is advised by a

19 number of groups, and it's supported by a staff. That

20 staff is led by Dave Skeen. They're not expected to

21 do all the work of implementing the recommendations,

22 but they're expected to run air traffic control, and

23 Amy is currently on that team. It's a team of what,

24 about six or eight folks, something of that nature.

25 So, Dave Skeen is a key individual in
81

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 this. Marty has clearly articulated his expectation

2 that NRR will be the lead implementing organization

3 and coordinating organization. For that reason, Dave

4 is currently reporting to Eric Leeds, and Eric will

5 have a very strong role in this going forward. So, the

6 presentation on the 45-day paper will likely involve

7 Dave, or Eric, or others once that paper goes forward.

8 CHAIRMAN ABDEL-KHALIK: Thank you. Are

9 there any questions for -- 

10 VICE CHAIRMAN ARMIJO: Yes, I have one.

11 Going back to Recommendation 7, other than being a

12 distraction to the operators during Fukushima, the

13 spent fuel pools turned out not to have been the

14 source of significant radiation release, if any. And

15 the earlier assessments during the accident or during

16 the events were that they were in serious trouble, and

17 it turned out not to be the case. So, I was just

18 wondering why -- some of the recommendations you make

19 about improving makeup capability and instrumentation,

20 those are all good things to do, but you're proposing

21 orders which seems like a very heavy regulatory hammer

22 for something that was not, in fact, a safe -- you

23 might even argue that it demonstrated the ability of

24 the old pool designs to protect health and safety. So,

25 I'm just wondering why there was, in your view, a need
82

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 for an order for this issue.

2 MR. GROBE: Yes, let me talk a little bit

3 about the spent fuel pools, and then talk about our

4 regulatory structure a little bit, and you guys can

5 help.

6 The spent fuel pools in Japan at Fukushima

7 Dai-Ichi contained between 150 and 500 assemblies,

8 something like that. They have a seventh spent fuel

9 pool in a different building that's separate, and they

10 move fuel from the spent fuel pools that are in the

11 reactor -- associated with each reactor to this other

12 spent fuel pool. So, that's very different from an

13 operational perspective than the way we do things here

14 in the United States.

15 Our spent fuel pools contain anywhere from

16 2,000 to 5,000 assemblies. And, of course, the heat

17 load is much more than that during a refueling outage.

18 So, from a certain perspective the spent fuel pools

19 were in a much different condition in Japan than our's

20 are here in the United States, as far as heat load.

21 But specific on regulatory structures, we

22 have four clear opportunities on how tools to collect

23 information, and we have two tools to require

24 licensees to do things. Our tools to collect

25 information are a NAM for information, a 50.54(f)
83

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 letter, a bulletin, and a Generic Letter. And they

2 have different purposes, but they were all sired from

3 the same law, okay? So, that the underpinning legal

4 structure is the same for all four of those tools.

5 Those tools cannot impose requirements,

6 they can only ask for information. The only two ways

7 that we can establish requirements -- I guess there's

8 three ways that requirements can be established. A

9 licensee can request that a requirement be imposed on

10 them through licensing, and we typically call those

11 license amendments. But the only way that we can

12 impose requirements on licensees is either through an

13 order, or through a rulemaking.

14 The rulemakings take at best -- the best

15 we've done with any rulemaking is 23 months, and

16 typically it takes substantially longer than that

17 because of the administrative procedures that are

18 necessary to engage people, and make sure that you're

19 doing it properly, develop the guidance so everybody

20 understands the regulation. And then the

21 implementation of the rule takes years after that,

22 especially if it involves modifications.

23 So, the intention of the Task Force was to

24 establish regulations. It's clear from the Task Force

25 study of this that voluntary initiatives have mixed
84

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 outcomes. There was a -- we have a number of little

2 stories, but one of them was you can only expect what

3 you inspect, and we only inspect what is required.

4 And we found that with the SAMGs, there was a spectrum

5 of behaviors among the licensees, and those were

6 voluntary. 

7 So, the Task Force concluded that these

8 things should be requirements, and the ones that are

9 orders it's not that they're imminent threats, it's

10 just that those -- that's our only tool to establish

11 a requirement in the near-term. 

12 VICE CHAIRMAN ARMIJO: Okay, thank you.

13 CHAIRMAN ABDEL-KHALIK: Thank you. At this

14 time, I'd like to call on Mr. Adrian Heymer from the

15 Nuclear Energy Institute to make some remarks. We have

16 received a copy of written remarks made by NEI, which

17 were actually provided to the Staff after the August

31st meeting. They're dated September 2nd 18 , so everyone

19 has seen these remarks. Mr. Heymer.

20 MR. HEYMER: Thank you, Mr. Chairman. My

21 name is Adrian Heymer. I'm the Program Manager for

22 the Regulatory Response to the events at Fukushima

23 from the U.S. perspective, and I appreciate having the

24 opportunity to chat with you today.

25 What I'm really going to cover is a little
85

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 bit of -- repeat a little bit of what we covered on

the August 31st 2 meeting, and open it up for questions.

3 And I think most of you are aware that since the

Fukushima events started to unfold on March 11th 4 , the

5 industry mobilized and has been engaged in that

6 activity. 

By Sunday, the 13th 7 we had a team in

8 Tokyo, and a team has been in Tokyo since, and has

9 been subsequently reinforced, and has been working and

10 is now embedded in the Tokyo Electric Power Company's

11 offices to really, one, to provide advice and

12 assistance and support during the event as it was

13 needed, and as requested. And, two, to feed back

14 information back to Atlanta to the Institute of

15 Nuclear Power Operations so that we could better

16 understand what was going on, what caused the events,

17 why they made the decisions they made. 

18 And really since about the second week or

19 first week of April, we've had a team trying to

20 reconstruct the events as they happened, trying to put

21 together a time line to make sure that we take the

22 correct action so we don't go down any cul de sacs as

23 regards our activities.

24 That team has concluded its activities,

25 but we have a lot of questions and open issues even
86

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 though we got the team embedded with TEPCO in Tokyo.

2 And they're going over next week to discuss the open

3 issues, and the questions that we have to try and find

4 out more about the basis and the rationale of what

5 occurred, what was the design basis, how they reached

6 that conclusion on the design basis.

7 So, I think that one of the messages we

8 don't really know everything that went on. We've got

9 a good idea. We have been surprised, and why we need

10 to move forward. And we can take -- and we agree with

11 a number of the Near-Term Task Force recommendations

12 that we need to move ahead, and we can in some

13 instances. In others, I think if we just food for

14 thought until we get the answers, and then a better

15 position to actually take action, it'll be more

16 beneficial, and more efficient and effective use of

17 our resources.

18 Therefore, we propose that at some stage,

19 probably once the team gets back and has finalized its

20 report, incorporating the insights from Japan, that we

21 sit down with the NRC Staff and go over what we see as

22 the time line to make sure that there is a common

23 understanding of what occurred so that we can go

24 forward with improving and enhancing the safety

25 margins for our facilities.
87

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 The other item, and it's been discussed

2 here today, is the need for flexibility. We do have

3 104 designs, different technologies, BWRs, PWRs,

4 different AEs, different geographic locations,

5 different credible risks that are posed for the

6 facilities. In some cases it may be a sandstorm, in

7 other cases it may be a flood, but it may not be that

8 the facility that's subject to a sandstorm might not

9 be subjected to a flood. So, I think we need some

10 flexibility going forward, and a risk-informed

11 performance-based approach would really sort of begin

12 to achieve that end.

13 We've made our comment in the letter, and

14 you've seen a copy of that, about why there's a

15 certain amount of uncertainty out there. We've done

16 a very high-level qualitative risk assessment of the

17 Task Force's recommendations to try to determine okay,

18 where is the biggest benefit both in terms of

19 protection, mitigation, and consequence. And by and

20 large, although in some areas there could be what we

21 call a moderate impact from a mitigation perspective,

22 in most of the other areas, especially in the

23 consequence areas it's small or negligible. 

24 So, why orders? And I think orders to us,

25 especially bold orders, and the criteria that are --
88

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 you have to develop to impose that order, from our

2 state of knowledge at the moment, it was a little bit

3 of a surprise, especially when there are other

4 vehicles that perhaps we can move forward with, and

5 have been successful in the past.

6 On the re-evaluation of the design basis,

7 seismic we believe -- we made a good start with GI

8 199, and we think that kind of gets us there. But

9 really what we need is not to wait, as we saw it, or

10 the way we read the report, and I thank Jack and his

11 team there for giving some clarification, to wait 10

12 years before we take action.

13 We believe that if you identify -- if

14 something is identified to you, there's new

15 information that comes along, and it could impact, you

16 need to assess that as regards its significance. We

17 do that today, we should continue to do that, and we

18 shouldn't wait 10 years to have a periodic update. It

19 should be on an ongoing basis just as we do today, so

20 we're not quite sure why we would want to go down that

21 path.

22 On extended loss of AC power, we made our

23 point about well, what's the rationale behind 72

24 hours, but we agree that we need to take some action

25 in that regard. But it's not as easy as it may appear
89

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 at first glance. And one of the things that we're

2 beginning to recognize, and we have task forces set up

3 in most of these areas -- and I would say that we

4 agree with the subjects, perhaps the vehicle and how

5 far we're going at this point in time is probably

6 where we've got a slight variance. 

7 But as regards extended loss of AC power,

8 as we call it, the operator has to start making the

9 decision in the first hour, especially as regards if

10 he's in this condition because he wants to make sure

11 the batteries are going to last as long as possible,

12 so we've begun to look at what would it take to get us

13 to eight hours, in fact, what would it take to get us

14 to 24 hours, because we agree with the Near-Term Task

15 Force that the operators really need to focus on

16 stabilizing the reactor. And if we can increase that

17 focus by not having to worry about certain other

18 areas, that is beneficial.

19 I think as regards new plants, we were a

20 little surprised to see the fact that you have to go

21 beyond 72 hours, and we were wondering why an

22 additional requirement was being imposed on new

23 plants. And the fact that it appeared to us from

24 reading the report that ITAAC is being used to impose

25 new requirements, and we don't think that's the right
90

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 vehicle.

2 There are advances on new plants, I think

3 you recognize that in the Task Force report, and so

4 what we believe is that new plant designs and

5 activities should be evaluated on a case-by-case basis

6 because you have much improved designs both from the

7 passive perspective, and from the designs like the

8 AREVA EPR and the Mitsubishi APWR, that have bunkered

9 systems and better protection.

10 On venting, I'm not sure from our

11 evaluations and the evaluations at INPO we really know

12 what was the rationale. We know they had problems.

13 Why they had problems and what worked and what didn't

14 work, and what was the path of hydrogen, we just don't

15 know. So, I think at this stage we would agree that

16 you can go -- we should go forward and say okay, can

17 we access the valves, can we operate the valves given

18 a loss of AC condition. But to go much further at

19 this point, we don't think we should go down that path

20 until we have more information. And hopefully by the

21 end of the year, we will have that information, and we

22 can go forward with those discussions.

23 On the spent fuel pool, I mean, that's an

24 area where we thought we knew what had happened. And

25 now we know it's a -- we were wrong. There were a lot
91

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 of people, including many in the industry, that

2 believed there had been a spent fuel pool accident.

3 And, in fact, from the sampling and the visual

4 inspections that have occurred in this last month, we

5 now know that that doesn't appear to be the case.

6 So, I think we do have time. We do agree

7 that we should be able to monitor the fuel pool and

8 the condition of the fuel pool. And that's something

9 that we need to move forward with, and the industry is

10 beginning to look at that hard. But we don't really

11 understand why it has to be safety-related.

12 And if you look at what happened at

13 Fukushima, we do have time, even though I agree with

14 the Task Force, that our reports are higher fuel

15 inventory than what we have in Japan, but we still

16 have time. And we've taken some action as regards

17 making sure that the operators are aware of time to

18 reach 200 degrees Fahrenheit in the pool as a sort of

19 improvement and enhancement. But we don't really

20 understand why the power supplies have to be safety21 related, because if they'd been safety-related in

22 Japan, you'd have been in the same position. So, I

23 think based on that aspect, we certainly can move

24 forward with monitoring.

25 On EOPs and SAMGs, a lot of discussion you
92

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 had here this morning, and I think, Dan Dorman, I

2 think you got it right where we're coming from. It's

3 not the fact that we want to take the decision making

4 necessarily away from the operators, but once you get

5 out there into extremely low probability events, don't

6 expect the operators to have the same degree of

7 knowledge that they do for the more likely events,

8 such as the EOPs, abnormal operating, and normal

9 operations.

10 So, I think there is need for training,

11 additional training, especially on the emergency

12 response organization. But what confused us a little

13 bit is when we started talking about Tech Specs, and

14 operator exams. And if you're going to start quizzing

15 operators as regards severe accident management

16 guidelines to the same details as you're quizzing the

17 operator about abnormal operations, or EOPs, that's

18 expecting a lot, and I think you're going to dilute

19 the capability of the operational response.

20 On EP, basically, our -- because I'm

21 running out of time, our message here on EP is let's

22 implement the new rule that's being put in place that

23 is an improvement, does implement certain

24 enhancements, and at the same time let's begin to move

25 forward in parallel with some of the recommendations
93

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 that have been made as regards EP.

2 As regards multi-unit staffing, we don't

3 think we can deal with multi-unit staffing and develop

4 the scenarios and the criteria in the time frame that

5 would enable us to be able to implement the rule

6 that's about to be introduced in the time frame that's

7 being suggested for that element. So, we may have to

8 have an extension if that -- if we want to make it

9 part of the new rule.

10 If that is a require -- we think most of

11 the recommendations can be implemented through

12 guidance, but if there is a need for rulemaking, we

13 can deal with that at a later date.

14 That's fundamentally the 10-minute -- 

15 CHAIRMAN ABDEL-KHALIK: Thank you, Mr.

16 Heymer. Are there any questions for Mr. Heymer?

17 MEMBER POWERS: Yes, I'd like to just ask

18 him one question, maybe broader, as well. 

19 In the area of hydrogen control in the

20 reactor building when we did the hydrogen rule, we

21 presumed that by inerting the drywells that we got out

22 of the hydrogen problems. And Fukushima demonstrated

23 that's not the case. And we don't have what I'd say

24 definitive evidence of why the hydrogen got into the

25 building, but people have been relatively imaginative
94

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 in coming up with pathways which hydrogen -- and I'm

2 wondering is not that proliferation of imaginative

3 methods by which hydrogen could get in there enough to

4 tell us that we need to do something about hydrogen

5 mitigation in the reactor building? 

6 MR. HEYMER: I think from our perspective

7 once we've determined, or at least got a better idea

8 of what was the path of hydrogen getting into the

9 reactor building, I think as a long-term evaluation we

10 should then take a look at hydrogen to address some of

11 the thoughts that you began to introduce, Dr. Powers,

12 as regards hydrogen and where it comes from. But I

13 think central to that is how did the hydrogen get to

14 where it got to to cause the explosion.

15 MEMBER POWERS: What I'm arguing is that

16 they're going to need to know exactly the path,

17 because the next accident that comes along will

18 undoubtedly take a different path. And people have

19 come up with gee, at various points I think I had 20

20 paths listed down. And presumably they'll have some

21 probability of occurring, maybe not at Fukushima, but

22 at some other accident. 

23 Isn't that enough to tell us well,

24 inerting can do it, and we should do for the reactor

25 buildings in ones and twos the same thing we've done
95

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 for reactor buildings in threes.

2 MR. HEYMER: I think that's something that

3 the evaluation will take a look at, and assess as we

4 go forward. I mean, that's something you can't ignore.

5 MEMBER BANERJEE: I think Dana's point that

6 the path will be specific perhaps to Fukushima, and

7 the next time around it will be something else, and

8 the next time around will be something else. We know

9 that hydrogen is a problem, whether it was in Three

10 Mile Island or Fukushima, and we should take care of

11 it.

12 MEMBER POWERS: Not only do we have a

13 hydrogen -- we've got hydrogen detonations. And

14 detonations are just extraordinarily hard to get. I

15 mean, even when you do them in an experiment, you have

16 a tough time doing a detonation because of

17 the ignition problem. And we got them, and it just

18 strikes me that gee, how much information do I need to

19 know about specifically Fukushima. I got hydrogen. I

20 see lots of ways of getting hydrogen. Go take care of

21 it. We did it for Mark IIIs, why can't we do the same

22 things for ones and twos. It's obvious that inerting

23 is just not enough.

24 CHAIRMAN ABDEL-KHALIK: Dennis?

25 MEMBER BLEY: Yes, I wanted to ask you a
96

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 question about the SAMGs. First, we did talk to INPO

2 about the same thing, and as part of your answer I'd

3 like you to discuss a little bit about the

4 relationship between NEI and INPO, and how you're

5 moving forward. 

6 But what's your view of the fact that when

7 NRC asked people to look at the SAMGs, that from my

8 reading of the list, I think there were only about two

9 plants that didn't have some kind of deficiency when

10 they reported back. Can you tell us a bit about what

11 you guys think about that, and how fast we're heading

12 to deal with those issues?

13 MR. HEYMER: Well, I think not only are you

14 aware when we identified those issues, that was a

15 surprise, and it's surprises like that that we can do

16 without. And we're fixing them. The majority of those

17 issues have been sorted out and fixed, but it's quite

18 clear that we need to do more on training. And I

19 think that's an awareness, and that's something that

20 we need to work on. And INPO has taken that item and

21 as regards the -- to see what we can do better about

22 implementing a training program to make sure that

23 operators and especially emergency response

24 organization personnel are better prepared and more

25 aware of what's in the SAMGs, and to make sure that we
97

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 keep the SAMGs current, they don't just become dust

2 collectors.

3 MEMBER BLEY: Is there concern in the

4 industry about the things we had heard from the Task

5 Force last time we met with them about the kind of

6 mixed messages they picked up, and I think others of

7 us have picked up about how various plants are dealing

8 with the Command and Control issue should you have to

9 actually start trying to use the SAMGs?

10 MR. HEYMER: I think Command and Control,

11 the SAMGs, and that whole area is something that we

12 put the procedures and the necessary controls in

13 place. Some people are focused on it more than

14 others, and we just need to raise that level within

15 the industry up to where those -- I wouldn't say it

16 was one or two, I'd say it's more than one or two have

17 got a good handle on it, but we just need to raise

18 that level of implementation and awareness up.

19 MEMBER BLEY: Is there guidance on this

20 issue?

21 MR. HEYMER: There will be -- it will be

22 developed.

23 MEMBER BLEY: Okay.

24 MR. HEYMER: I mean, we're working -- INPO

25 is working on that. They identified it, and the Chief
98

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Nuclear Officers were made very much aware of this is

2 an area that we need to focus on. So, it's being

3 addressed. It's in the Corrective Action programs, and

4 we need to go down to make sure that we don't get

5 surprises like that going forward.

6 MEMBER BLEY: Thanks, Adrian.

7 CHAIRMAN ABDEL-KHALIK: Thank you. We are

8 10 minutes behind schedule, so thank you very much for

9 a very informative presentation.

10 MEMBER CORRADINI: Don't we have somebody

11 on the lines?

12 CHAIRMAN ABDEL-KHALIK: No, we don't. So,

13 at this time we will take a break for 15 minutes, and

14 we will reconvene at five minutes to 11:00 for the

15 next item on the agenda.

16 (Whereupon, the proceedings went off the

17 record at 10:39:15 a.m., and went back on the record

18 at 10:52:47 a.m.)

19 CHAIRMAN ABDEL-KHALIK: We're back in

20 session. At this time we will move to the next item

21 on the agenda, "Technical Basis and Rulemaking

22 Language Associated with Low-Level Waste Disposal and

23 Site-Specific Analysis." And Dr. Ryan will lead us

24 through that discussion.

25 MEMBER RYAN: Thank you, Mr. Chairman.
99

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Good morning to participants. I will quickly turn

2 over the meeting to Deborah Jackson, who will make

3 some introductory remarks. And then we will have the

4 more technical briefings and have questions and

5 answers from there.

6 So, without further ado, Deborah Jackson

7 from FSME.

8 MS. JACKSON: Thank you, Mike. Good

9 morning, members. We are here today to give you an

10 update on the work with Part 61.

11 And why we are here today is were are

12 following Commission direction. And what we were

13 doing is proposing rulemaking limited to site-specific

14 analysis, identifying the technical requirements of

15 the analysis, and developing guidance outlining key

16 parameters of assumptions. And this approach

17 continues to protect public health and safety. It's

18 risk-informed, performance-based. And it also

19 provides flexibility to licensees and corporate

20 site-specific information.

21 We're going to have two presenters from

22 staff today: first, David Esh. And he will be

23 providing a discussion on the "Guidance for Conducting

24 Site-Specific Analyses for Part 61." And Andy Carrera

25 will wrap up the staff presentation. And he will do
100

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 an analysis of the comments received on the

2 preliminary rule language.

3 So, with that, I will turn it over to

4 David.

5 MR. ESH: Thank you.

6 It is my pleasure to be here again to talk

7 about Part 61 and what we are doing in the rulemaking.

8 Next slide, please. Just to refresh your

9 memory, I will go over what our direction was from the

10 Commission. The direction from the Commission was

11 that we were supposed to perform a limited rulemaking

12 to add site-specific analyses prior to the disposal of

13 significant quantities of depleted uranium and blended

14 waste. And as part of that, we were supposed to

15 identify the technical requirements that would apply

16 to the site-specific analyses and develop a guidance

17 document that outlines the parameters, assumptions,

18 and those sorts of things in conducting such

19 site-specific analyses.

20 The requirements I feel that we have

21 developed are appropriate for this limited-scope

22 rulemaking. And the bottom line to me is that they

23 have to be able to distinguish between an action that

24 is appropriate and an action that is inappropriate.

25 Hopefully I'll try to convince you of that as we go
101

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 along.

2 We weren't tasked with modifying the

3 framework for Part 61 in this activity. That is a

4 future activity that we could consider changing the

5 framework. So questions about framework, we're

6 welcome to take them, but we feel we are on pretty

7 strong ground with not modifying the framework in this

8 limited-scope rulemaking because the Commission did

9 express a desire that it gets done relatively quickly;

10 that is, relatively quickly in government terms.

11 So this rulemaking -- next slide, please

12 -- what we do is we require site-specific analyses to

13 demonstrate compliance with the Subpart C performance

14 objectives. We identify the technical requirements

15 for the analyses. So basically I would describe it as

16 we have definitions of what those analyses are.

17 And then the two main requirements that we

18 have changed as part of this rulemaking are the

19 addition of the period of performance and the Intruder

20 dose criterion.

21 At a higher level, the only main thing

22 that we have changed is adding in the requirement for

23 an intruder dose assessment to meet the 61.42 61.42

24 performance objective.

25 As part of this activity, we have
102

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 developed a guidance document -- we have briefed the

2 Subcommittee on that at a previous meeting -- that we

3 feel is risk-informed and performance-based. And it

4 outlines the key parameters and assumptions in doing

5 these sorts of evaluations.

6 The overall rulemaking effort, we believe,

7 continues to protect public health and safety while

8 providing flexibility to licensees.

9 VICE CHAIRMAN ARMIJO: David, just to make

10 sure that I have it right, the Subpart C performance

11 objectives, are they changed or not with the limited

12 --

13 MR. ESH: There are four performance

14 objectives, 61.41 through 44. 61.41 is basically

15 protection of a member of the public. And that we

16 have not changed. The only change to it is adding in

17 the period of performance, which we -- it was

18 expressed to us by stakeholders in various

19 interactions that they wanted it in the rulemaking.

20 They couldn't agree on a number, but they wanted it in

21 the rulemaking.

22 The 61.42 performance objective is not a

23 new objective, but the component added to it that is

24 new is the intruder dose assessment. So the existing

25 performance objective requires that you meet the waste
103

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 classification and segregation requirements, which is

2 done through tables in 61.55 in the regulation for

3 radioisotopes that are listed in the tables.

4 What we did in this rulemaking for

5 isotopes that are not listed in the tables, the

6 options previously presented to the Commission were to

7 revise the tables and add in the new isotopes, to take

8 the approach we did with a site-specific analysis

9 requirement to change the whole waste classification

10 system, which is kind of what is being proposed or

11 what is being discussed in the comprehensive

12 rulemaking context or do nothing. I think those are

13 the four main alternatives. And the Commission

14 directed us to take the action that we are taking in

15 this limited-scope rulemaking.

16 VICE CHAIRMAN ARMIJO: Okay. The period

17 of performance and the intruder dose assessment are

18 major changes --

19 MR. ESH: Yes.

20 VICE CHAIRMAN ARMIJO: -- in the

21 performance objectives?

22 MR. ESH: Yes. The performance objectives

23 have not been changed, but 61.41 has been. We have

24 changed the -- it didn't use the performance

25 assessment terminology before, but, in essence, it was
104

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 a performance assessment. Performance assessment

2 terminology I would say developed after the early

3 '80s, when the regulation was developed.

4 What we did was modernize the terminology,

5 but in the 61.42 performance objective, we're adding

6 in the requirement to do the intruder dose assessment.

7 So that's the new part of it. And then a period of

8 performance is applied to both of those. So that is

9 also in there.

10 MEMBER RYAN: That's a big change. That's

11 changed from 10,000 to 20,000 units.

12 MR. ESH: Well, the existing regulation

13 has not value for a period of performance. It's

14 silent. The regulation is silent on what the period

15 of performance is. And this created a lot of variance

16 in our agreement state programs.

17 MEMBER RYAN: The guidance was now --

18 MR. ESH: The guidance was we had

19 NUREG-1573 --

20 MEMBER RYAN: Right.

21 MR. ESH: -- guidance, which recommended

22 10,000 units.

23 MEMBER RYAN: Right.

24 MR. ESH: But there's no value in the

25 regulation. And our agreement states did not
105

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 necessarily all follow the guidance. They did what

2 they wanted to in their agreement state programs.

3 VICE CHAIRMAN ARMIJO: But prior to these

4 amendments, there was no requirement for an intruder

5 dose assessment.

6 MR. ESH: Prior to these requirements,

7 there was no requirement, there was no explicit

8 requirement, for an intruder dose assessment. But the

9 NRC basically did an intruder dose assessment in

10 developing the 61.55 waste classification tables.

11 So there's one implicit in the regulation

12 but not explicit. And what we did is we added an

13 explicit requirement for that for isotopes that aren't

14 in the table, basically to apply the same analyses to

15 the isotopes that aren't in the tables as the analyses

16 that was applied to develop the tables.

17 Next slide, please. So what we didn't do

18 in this rulemaking effort, we haven't done, is update

19 the waste classification tables. That was an option

20 presented to the Commission. And they said not to do

21 that. We also are not comprehensively revising the

22 framework.

23 So we have had lots of questions about the

24 framework, both from the ACRS and our various other

25 stakeholders, on things like the performance
106

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 objectives. You know, does it make sense to do an

2 intruder assessment? What should be the institutional

3 control period, things of that nature? And we felt in

4 this limited-scope rulemaking, we shouldn't be

5 revising the framework. It is certainly things that

6 we could consider in a comprehensive effort.

7 And the Commission directed us to propose

8 resources to do such an effort. Of course, those

9 resources also have to be allocated after we proposed

10 the resources.

11 So we didn't do things like remove the

12 protection of the inadvertent intruder performance

13 objective. But what we have done, I believe is

14 provided some flexibility for how people can meet

15 these requirements to allow some bringing in the

16 site-specific nature of the problem that you're

17 dealing with here.

18 So next slide, please. The proposed

19 amendments for the site-specific analysis, as I

20 already went over the first couple, we have a

21 performance assessment to demonstrate compliance with

22 protection of the general population in 61.41. I

23 would maintain that this is not a new requirement. We

24 have just changed the terminology. It was previously

25 called technical analyses, I believe.
107

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Under 61.42, as already noted, we add the

2 requirement for an intruder dose assessment, in

3 addition to the waste classification and segregation

4 requirements.

5 MEMBER RYAN: A couple of points on that

6 one. I think it's important for the Committee to

7 recognize that the probability of intrusion is one and

8 the period of performance is doubled from 10 to 20

9 thousand units. Those are two key facts that you need

10 to understand.

11 MR. ESH: Yes. I know we have some maybe

12 difference of opinion about the probability of

13 intrusion because I would maintain that the intruder

14 dose assessment, as I'll talk about in a few slides

15 here, we're recommending a dose limit of 500 millirem

16 for that evaluation.

17 The dose limit that is used under 61.41 is

18 25 millirem. So there's an implication in the numbers

19 -- and the Commission stated this in both the draft

20 EIS and the EIS, but the intruder part of the problem

21 is unlikely, viewed as unlikely, albeit possible. So

22 that's the justification or part of the justification

23 for applying a higher dose limit for the intruder

24 evaluation.

25 If you thought the intruder evaluation was
108

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 probability one, you wouldn't really have much of an

2 argument to choose a dose limit other than the 25 that

3 you apply to 61.41 because why if you're drawing an

4 imaginary line on the ground as to where the facility

5 footprint is do you say one dose limit applies on one

6 side of the footprint and one dose limit applies on

7 the other side of the footprint?

8 Sure. Go ahead.

9 MEMBER STETKAR: You used the term

10 "unlikely but probable" or something like that.

11 MR. ESH: "Albeit possible" is the

12 language the Commission.

13 MEMBER STETKAR: "Albeit possible." If I

14 do the math, that says there's a five percent

15 probability, which we can argue about what is likely,

16 but --

17 MR. ESH: Yes.

18 MEMBER STETKAR: -- it's not a 1 in 1,000

19 --

20 MR. ESH: Yes.

21 MEMBER STETKAR: -- possibility that we

22 might get an intruder residing on that site for its --

23 MEMBER RYAN: And you could take another

24 view to say that if you have a continue of 12 feet in

25 diameter in the 400-acre site, you probably are
109

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

hitting it at 3 times 10-6 1 .

2 MR. ESH: Yes. And I hope for our talk

3 we'll whenever we get to the guidance in a few slides

4 here give you a better flavor for how we're

5 recommending people develop the scenarios and the

6 analysis, but this issue of what is the probability of

7 that scenario and is it even reasonable to consider,

8 right now it's very subjective.

9 We're trying to do some things to make it

10 a little more objective. So there's a member in my

11 group that's an expert in GIS. And I have him working

12 on a project to look at disturbance maps over the

13 country, both with space and time, and use that to try

14 to estimate in the recent historic past, at least

15 multiple decades. What sort of disturbance do you

16 expect over different types of areas and into

17 different depths? That isn't developed yet.

18 MEMBER RYAN: Would that be focused on

19 licensed facilities?

20 MR. ESH: Well, the issue is then how

21 durable are the additional protections that you put in

22 for a licensed facility to prevent that sort of

23 disturbance from occurring. So the one point you can

24 get at easily is what is the disturbance that you

25 observed due to development, socioeconomic activity,
110

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 and everything? But the part that is much more

2 difficult to get at is how durable are those

3 additional controls that you put on to try to prevent

4 those activities?

5 And the Commission does put controls on,

6 as you are well-aware: institutional controls, state

7 and government land ownership. There's a whole bunch

8 of defense-in-depth-type things they put in place to

9 try to prevent somebody from using the site in the

10 future.

11 But they say over these long time frames

12 that you're dealing with, durability of records,

13 government error, those sorts of things, it's not a

14 completely unforeseeable event that somebody could use

15 a site, but it is probably unlikely. How unlikely?

16 I don't really know.

17 MEMBER RYAN: I'm sure there's a range

18 there, but if you look at the low-level waste sites,

19 the radioactive material waste sites that are around,

20 that's probably the ground you want to plow first.

21 MR. ESH: Yes.

22 MEMBER RYAN: I mean, for example, a case

23 I know fairly well is Barnwell. And right now they're

24 in a position where their financial resources, the

25 interest on them is more than what they use annually
111

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 to maintain the site. So it's hard to envision where

2 they will run into a lack of ability to keep track of

3 that for --

4 MR. ESH: I think that's a very good

5 point. I think the problem becomes very difficult

6 over long term. You get into situations like -- and

7 this happens with monitoring of these types of

8 facilities over long periods of time. As you monitor

9 in the near -- in the present future after you have

10 taken your action, if you did a good design and

11 implemented a good design, and put it in place in the

12 right way, you're probably not going to see anything

13 in your monitoring program.

14 So, after so many years of monitoring zero

15 so people will have the tendency to say, "Well, why am

16 I monitoring this anymore? I'm not seeing anything

17 out of the facility," but because of the degradation

18 and changes to the facility over time, it's exactly as

19 you go out in time where you might expect to start

20 seeing something.

21 See, you have these complicated structures

22 of the problem that will influence what people do with

23 those resources that they allocate to control the

24 site. So at some point, somebody in the realm that

25 has some ability to do something with those funds may
112

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 say, "I am going to more productively use those funds

2 for something else."

3 MEMBER RYAN: That is always a risk. But

4 I think the other part of it is, even over a long

5 time, like a legislative period of a 100-year

6 performance interval that has to be funded, you not

7 only get into the monitoring, you're into maintenance.

8 So maintenance activities I think feed the monitoring

9 with good results. So I don't think it's a simple,

10 you know, a given that over time people will want to

11 take the money and do something else and present it at

12 the waste site.

13 MR. ESH: I don't think it's a given

14 either. I think it's one of the things that you could

15 expect may occur.

16 MEMBER RYAN: My experience would lead me

17 to think it's much less likely than not that they

18 would continue on.

19 MR. ESH: Yes. We don't have -- because

20 we don't have a lot of knowledge of actions that have

21 been taken in terms of, say, people trying to dispose

22 or isolate material -- you know, the U.S. is only

23 about 250 years old. So you don't have a lot of

24 information on people taking actions to try to dispose

25 of materials and then what happens as you go forward
113

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 in terms of controlling those locations and land use

2 of those locations over time.

3 I don't claim to know the answer on it.

4 All I can do is explain the logic behind the existing

5 regulation and why that framework is in place.

6 VICE CHAIRMAN ARMIJO: David, just a

7 little bit. Where did the 500 millirem come from?

8 Was that arbitrary or --

9 MR. ESH: No. The 500 millirem when it

10 was initially selected was consistent with 10 CFR Part

11 20 at the time. So basically they were taking this

12 concept that the intruder was unlikely, but they also

13 wanted to be consistent with an existing other

14 requirement.

15 Of course, 10 CFR Part 20 is now 100

16 millirem. And we have had comments on that by

17 stakeholders. They said, "Well, you should make it

18 100." We were recommending 500 because then the

19 numbers that you're generating in the intruder dose

20 assessment are consistent with the 500 millirem that

21 was used to develop the 61.55 table values.

22 So we had to choose one way or the other.

23 We chose to go that way.

24 VICE CHAIRMAN ARMIJO: A number that you

25 used to develop the table?
114

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. ESH: Yes, the same number that we

2 used to develop the tables.

3 MEMBER RYAN: I think it is important to

4 recognize that that number is -- and I don't mean this

5 as a criticism of what you did, but it's kind of

6 arbitrary in terms of risk. A hundred millirem, 200

7 millirem, 500 millirem, it's not a big variation. We

8 can pick them --

9 MR. ESH: That's part of like if I think

10 you're going to go -- my belief is you should consider

11 some sort of tiered performance period and dose limits

12 to handle this type of problem and the uncertainties,

13 but if you're constrained by only considering, say, 25

14 millirem and 100 millirem for very long times, then

15 what is the point of that? They aren't materially

16 different in my mind for these types of problems and

17 the uncertainties you are talking about.

18 MEMBER RYAN: That's right. Well-said,

19 yes.

20 MR. ESH: Yes. And so I agree with you

21 there.

22 Next slide, please. I'm sorry. Go back

23 a second. I didn't get to the third bullet here,

24 "Long-term analyses." That is a new requirement. And

25 it's not -- as far as to the post-20,000 years period.
115

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 And it's to show how your facility and site have been

2 engineered or will perform to try to limit those

3 long-term impacts, but we aren't proposing at this

4 time a dose limit associated with those long-term

5 impacts.

6 And that we feel is consistent with a lot

7 of what you'll see in international programs, where

8 they recognize the uncertainties and they say, "Okay.

9 It may not make as much sense or it may not make sense

10 to say what a radiological impact is over those very

11 long times." You should be able to from an

12 engineering and scientific sense show how your

13 facility is limiting fluxes and concentrations and

14 those sorts of things over long periods of time.

15 MEMBER RYAN: To me, that can -- correct

16 me if I am wrong. I am just trying to get the other

17 members some examples. That's kind of the exact one.

18 It's probably not good to put it in a river delta that

19 is migrating toward you --

20 MR. ESH: Yes.

21 MEMBER RYAN: -- and those kinds of

22 things, where over those sorts of time horizons,

23 intrusion by natural processes into the disposal site

24 is more likely than not or has -- you know, it looks

25 like things are coming your way, for example. That
116

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 would be one thing you want to avoid.

2 MR. ESH: The other thing I would add is

3 that the long-term analyses only applies to when you

4 have significant amounts of long-lived waste. It

5 doesn't apply to all waste in all facilities. So it's

6 only in analyses that if you say, "I have long-lived

7 waste," okay. Show me how your facility and your site

8 are going to act to try to reduce the fluxes and

9 concentrations that you may have associated with that

10 long-lived waste.

11 MEMBER RYAN: The old question, of course,

12 is what is a significant amount.

13 MR. ESH: Yes. Well, I mean, I'll show

14 you --

15 MEMBER RYAN: Okay.

16 MR. ESH: -- maybe some examples or at

17 least I'll talk a little bit about it.

18 So let's go on to the next slide, please.

19 So in the proposed technical requirements, we have

20 performance assessment, which identifies the features,

21 events, and processes which comprise your evaluation.

22 The features, events, and processes are those

23 components that determine that scope of your

24 evaluation and you look at the effects of the

25 features, events, and processes on the performance of
117

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 the disposal system.

2 The performance assessment estimates the

3 annual total effective dose equivalent, TEDE, to any

4 member of the public considering uncertainties, caused

5 by the FEPs that you include in your assessment.

6 And then associated with the performance

7 assessment we have a two-tiered period of performance.

8 The first tier is to estimate the peak annual dose

9 that occurs within 20,000 years. So basically if you

10 have a facility to add short-lived waste, you can show

11 when the peak occurs, make some argument that you have

12 captured the peak, and that's what you need to do to

13 meet the requirement.

14 As I already noted on the previous slide,

15 we have a requirement for the post-20,000 years to

16 show us how the facility and the site are working to

17 limit the risk from your long-lived waste.

18 VICE CHAIRMAN ARMIJO: How can you claim

19 any credibility for something that 20,000 years into

20 the future? I mean, who would believe it? Material

21 degradation, environment changes. You know, I'm just

22 having a real hard time understanding what we gain

23 from regulating so far into the future when we can't

24 really demonstrate in any credible way, at least in my

25 opinion.
118

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. ESH: Well, there are strong and

2 diverse opinions about the credibility of those

3 analyses over those time frames. And in some cases,

4 I believe we -- in this sort of process, we aren't

5 necessarily capturing all of the uncertainties that

6 you're dealing with, especially in the societal and

7 technology components.

8 So how do societies and technologies

9 change over time? And how would that affect your

10 decision? But if you are trying to take a disposal

11 action, the approach that's taken, both that we're

12 recommending here and that's done internationally, is

13 to limit your speculation about the human component

14 and try to address the components that you think you

15 have a better handle on the engineered natural site

16 behavior components.

17 But I believe there are large

18 uncertainties. But the ability to reduce -- some of

19 the uncertainties are going to certainly be epistemic

20 that are reducible. Some are going to be aleatoric

21 and basically unreducible.

22 How much of each you have is a subject of

23 debate. And what we generally see is if you have a

24 performance assessment and you were talking about a

25 very long time and you're right around 25 millirem,
119

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 you probably have a difficult road ahead of you in

2 terms of convincing the decision-makers that you have

3 met the criteria.

4 The uncertainties are generally large that

5 don't allow for that sort of precision at those time

6 frames. But it is very possible to generate

7 calculations of those performance estimates. And in

8 our process, what is generally lacking and what we

9 pushed on strongly is you have to develop support for

10 your calculations.

11 So this problem is a little bit different

12 but not altogether different than some engineering

13 problems where you're trying to estimate, say -- I'm

14 on rotation right now through a group at research,

15 where we're looking at piping failure and they're

16 trying to estimate the probability of rupture or leak

17 before break and rupture.

18 And basically they don't have the ability

19 to validate those calculations in the true sense

20 because they don't have a lot of observations of

21 ruptures.

22 In this problem, we won't have

23 observations of doses to some future population at

24 20,000 years. But we do still require model support

25 to have confidence in that you generated -- you have
120

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 done calculations that are reasonable estimates of if

2 I brought some independent scientific and technical

3 people into the room, they could sit down and go

4 through the calculations and come to a similar opinion

5 and that the essence of model support is you take all

6 means necessary to develop the support for those types

7 of calculations.

8 It may involve experiments, lab

9 experiments, field experiments, natural analogs,

10 independent expert elicitation. There is a

11 multifaceted approach to developing support for your

12 calculations.

13 I don't necessarily disagree with you

14 about the uncertainties at these long times, but I

15 don't know how else you manage the problem. And the

16 approach that we're recommending is consistent with

17 what's done out there in this community.

18 MEMBER RYAN: The way you describe it,

19 though, David, that hump of -- you know, it's 25

20 millirem. Let's pick the number as the standard. The

21 uncertainties are such that you can't get over the

22 hurdle again. Why do you make a decision?

23 MR. ESH: Well, the issue is one of --

24 remember, low-level waste is the first step in the

25 waste management food chain. And one very
121

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 straightforward way to mitigate your uncertainties is

2 to modify the inventory that you take.

3 So if you want to dispose of large

4 quantities of long-lived waste and you do your

5 assessment and you say, "I have these vast

6 uncertainties" and I can't say what the risk is, then

7 maybe you should limit the inventory of those

8 components so --

9 MEMBER RYAN: Well, let's pick on -- the

one that stands out is at 109 10 year half-life

11 radionuclide. And in the one case, we're concerned

12 about low-level waste, as we discussed very well in

13 the context of what you said.

14 On the other hand, we take, you know,

15 milltailings and put it on the top of the ground, put

16 a little topsoil on it and grow grass on the top of

17 it.

18 MR. ESH: And I would say it's not the

19 same thing. They're materially different because the

20 milltailings are at about .2 weight percent uranium.

21 And the depleted uranium, if you take a lot of it and

22 dispose of it in a facility, you're talking about 80

23 weight percent uranium.

24 MEMBER RYAN: The inventory is much higher

25 in the tailings.
122

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. ESH: The inventory may be higher, but

2 --

3 MEMBER RYAN: It's the fraction released

4 from the inventory that gets to the dose.

5 MR. ESH: It's not just the fractional

6 inventory in totality. It's a combination of

7 concentration and quantity. So in the case of

8 depleted uranium, you have large quantities in very

9 high concentrations.

10 If the concentration is 500 times higher

11 than the milltailings, -- and milltailing facilities

12 are big, but they aren't. Some of them are massively

13 larger than what you have for --

14 MEMBER RYAN: Just to pick on DU for a

15 minute, if we have depleted uranium, which is a

16 concentrated form of uranium, 238 mainly, and I have

17 it in a steel container or a stainless steel container

18 and it's buried 30, 40, 50 feet deep, the probability

19 of getting to it is a whole heck of a lot less. It's

20 clear the magnitude would have an explosion for the

21 near term.

22 So it's not just concentration. It's

23 probability of being treated in a way that puts

24 whatever scenario you want. There hasn't been enough

25 contact to create a dose of concern.
123

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. ESH: The problem with depleted

2 uranium or concentrated uranium, in particular, is it

3 can get you in two ways. It can get you in the water

4 pathways. And it can get you in the air pathway.

5 So if you don't dispose of it deeply, as

6 the radon builds in over time, you end up with a lot

7 of radon, even just in the atmosphere. It doesn't

8 have to reply to the house being built above a

9 disposal facility. You get a lot in the atmosphere.

10 You also depending on the geochemical

11 conditions of your site can end up with significant

12 amounts of uranium in the water because it's a

13 concentrated source of uranium.

14 We see that in some cases now with our

15 milltailing facilities that you reference much lower

16 concentrations of uranium, but they have issues with

17 uranium in the water around those facilities.

18 MEMBER RYAN: It's actually buried on the

19 surface with a little bit of topsoil. Of course, you

20 would.

21 MR. ESH: Well, of course, but we have

22 research also from Craig Benson at the University of

23 Wisconsin that shows that the resistive engineering

24 covers, which are typically employed at these types of

25 facilities, they undergo pretty dramatic changes in
124

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 their properties over relatively short periods of time

2 compared to the characteristics of the material in the

3 analysis period that you're talking about here.

4 So it's very difficult to keep Mother

5 Nature at bay, especially in terms of her desire to

6 move water through the system.

7 MEMBER RYAN: I think you made the point

8 earlier unless you tend to that at the front end and

9 have an institutional program and funding and

10 intention to manage that, which you can do and it's

11 being done successfully at several sites --

12 MR. ESH: Yes. So next slide, please.

13 MEMBER CORRADINI: I just had one

14 itty-bitty little question. So you said the two

15 pathways. In my memory -- maybe I have the wrong

16 number, but isn't the 25 here somehow linked to what

17 EPA has for groundwater drinking in terms of it's on

18 that order of for other chemical releases or am I

19 remembering incorrectly?

20 MR. ESH: I think you're remembering

21 incorrectly. I mean, we are considering the impacts

22 to groundwater pathway in developing that number --

23 MEMBER CORRADINI: Right.

24 MR. ESH: -- and to air pathways. But

25 it's not related to EPA specifically. So I guess
125

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 maybe you're remembering somewhat correctly.

2 MEMBER CORRADINI: That's okay. I don't

3 get hurt easily.

4 MR. ESH: The concepts are there. We're

5 trying to protect all the pathways that may be

6 involved. We're not explicitly tied to any of the EPA

7 requirements in doing so.

8 MEMBER RYAN: Okay. I'm not trying to

9 match that number, but I think the methodologies have

10 alignment in some ways.

11 MR. ESH: Yes.

12 MEMBER RYAN: You know, it's not a merit

13 coming up with the same number in my view.

14 MEMBER CORRADINI: I was trying to get at

15 Sam's original question. Why is it that line? My

16 only memory is that EPA for groundwater drinking has

17 certain requirements for chemical releases that were

18 on the order of 10,000 years.

19 MR. ESH: It's partly that long. Well,

20 it's partly that long for a couple of reasons. And

21 I'll get into them in a slide here.

22 MEMBER CORRADINI: Okay. Fine.

23 MR. ESH: We can talk about them there.

24 VICE CHAIRMAN ARMIJO: I don't mean to

25 hold you up because I think eventually you are going
126

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 to talk about the public comment slides. And are you

2 going to discuss the Department of Energy comments?

3 MR. ESH: Yes, yes, yes. We didn't circle

4 back to that last time with MP 1 and 2.

5 VICE CHAIRMAN ARMIJO: Because, you know,

6 I want to bring that up and get that on the record

7 when the time comes.

8 MR. ESH: Sure. Next slide, please. So

9 then we also have the intruder assessment. It might

10 be more important because we have already talked about

11 this with you. To go by this quickly -- and I'll talk

12 about the detailed guidance and the scenarios of how

13 you go about doing this because I think that will

14 address some of your concerns hopefully to -- let's go

15 to the next slide.

16 All right. So technical basis for 20,000

17 years. We were just talking about this. There are a

18 number of elements that we considered in developing

19 this number. The first thing we looked about was

20 climate change or the stability of a near-surface

21 disposal facility.

22 What I want to emphasize is that we may

23 have had an initial value of, say, 10,000 years for

24 Yucca Mountain. And that was based on considering the

25 stability of a geologic system. And part of the
127

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 argument was if you're stable for 10,000 years in a

2 geologic system, you're likely going to be stable for

3 much longer.

4 That same logic doesn't apply in the near

5 surface. The near surface is much more dynamic. You

6 have to start worrying about geomorphology and all

7 sorts of things going on, but especially at more

8 northern locations, you have glaciation and climate

9 effects that come into play.

10 So while we try to be practical about

11 considering the climate effects, especially because

12 how is society going to be affected when climate

13 change does occur, we think that if you consider a

14 period of time like this and evaluate your facility,

15 it can allow you to make better decisions with respect

16 to long-term stability.

17 So if you're considering what happens at

18 these longer times, you're going to put waste and

19 locations that have more favorable characteristics

20 towards stability. And the NRC's approach to waste

21 disposal is concentrating contain. So we feel this is

22 in line with that philosophy.

23 The second element of this, of the

24 consideration for this period of performance, was the

25 radionuclide transport characteristics. We have
128

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 talked some about NUREG-1573 and how they developed

2 10,000 years.

3 The 10,000 years that were developed in

4 NUREG-1573 -- and I wouldn't take that number lightly

5 by any means, and we didn't -- that was a group of

6 experts that probably had hundreds of years of

7 performance assessment expertise that came up with

8 that number.

9 What they looked at is they said, "Well,

10 what do I need to understand how my system is working

11 and how changes in the engineered barrier system or in

12 radionuclide transport through the geosphere is going

13 to affect my problem?" And they came up with a

14 number of 10,000 years for that.

15 Part of the basis of that was looking at

16 radionuclide transport for a shallow humid site. They

17 only looked at one type of site. In this evaluation,

18 we looked at all types of sites, ranging from shallow,

19 humid, to deep and arid. And what happens when you

20 look at all types of sites, if you stretch out the

21 20,000 years, you'll better capture the radionuclide

22 transport characteristics at different types of sites,

23 as opposed to just a humid, shallow site.

24 So that pushed us in one direction for the

25 radionuclide transport characteristics. And then with
129

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 the specific direction that was given to us by the

2 Commission for depleted uranium, we looked at the

3 characteristics of depleted uranium.

4 Depleted uranium is much more benign when

5 it's just disposed of than it becomes over time. Over

6 time, the daughters grow in. And the risks from

7 depleted uranium at 1,000 years is about 1/1000th of

8 where it ends up whenever it reaches its peak. When

9 all the daughters --

10 MEMBER RYAN: Can you just explain the

11 basis for that factor of 1,000 increase? Because

12 that's a construct. That's not anything intrinsic to

13 the --

14 MR. ESH: No. It's the radiological

15 characteristics of the material with the ingrowth of

16 the daughter products.

17 MEMBER RYAN: It's one scenario of

18 exposure.

19 MR. ESH: Well, it would apply either to

20 anything that the daughter radionuclides can cause

21 impacts from. In this case, it's the air and the

22 water pathways or even direct exposure-type situations

23 but mainly the air and water pathways because you have

24 radon that comes in through the air pathway and --

25 MEMBER RYAN: To a theoretical house and
130

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 all of that.

2 MR. ESH: And you have --

3 MEMBER RYAN: You have drinking water and

4 every kind of water pathway where it's leaching at

5 some high rate.

6 MR. ESH: It will leach at whatever rate

7 is characteristic for that particular disposal

8 facility given the solubilities and the specific

9 surface area of the material you have disposed of --

10 MEMBER RYAN: I believe the other part is

11 -- correct me if I am wrong -- without much credit for

12 any longer-term barrier at all, I mean, assuming for

13 stainless steel, that has gone away at some point and

14 on the --

15 MR. ESH: I'm only talking on a relative

16 basis here. So at 1,000 years, whatever credit you

17 take for various things, you compare the material,

18 just its characteristics itself, to what you have at,

19 say, two million years or a million years. You were

20 talking about about a factor of 1,000 delta and the

21 potential risk from that material.

22 Whether the risk is realized depends on

23 the specific disposal configuration, engineered

24 barriers, all of the other things in the problem.

25 When you go to 20,000 years, you're within
131

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 about a factor of ten for depleted uranium. Because

2 you have had a lot of the daughters grow in, if you're

3 assessing 20,000 years in your regulatory analysis,

4 you don't run the risk that you are way off just

5 because of the characteristics of the material and its

6 ingrowth over time.

7 If you stop your analyses at 1,000 years,

8 you potentially have a factor of 1,000 still coming in

9 the system. So say you used 1,000 years and you have

10 the 61.42 intruder performance objective, you might be

11 around 500 millirem or you could be at 500 millirem at

12 1,000 years and you end up 1,000 times more than that

13 at some peak location.

14 That's a pretty big dose you're talking

15 about. You know, what does that mean over a million

16 years? And what should you be doing with it? That's

17 not for me necessarily to say, but I believe this

18 construct of going to 20,000 years handles that

19 problem because I can make an argument that

20 considering all the uncertainties, missing a factor of

21 10 for this one particular waste type if the system

22 evolves in a certain way, I'm on relatively firm

23 ground to make that argument.

24 But with most performance assessment and

25 waste disposal problems, they set their requirements
132

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 and they do their analysis based on the

2 characteristics of the material they want to take.

3 And depleted uranium can have another home somewhere

4 down the food chain if you can't meet the requirements

5 for near-surface disposal of large quantities,

6 concentrated amounts, shallow burial depth, you know,

7 however you wanted to solve the problem.

8 So that's the construct of the technical

9 basis for the 20,000 years. And I think we can

10 discuss it further when I get through some of these

11 other elements here.

12 VICE CHAIRMAN ARMIJO: Maybe you can help

13 me out here, David. I'm trying to understand it. If

14 we have depleted uranium, you're telling me that way

15 out in time, it's much more hazardous because both of

16 these powder products.

17 But let's take the case of just plain old

18 uranium, natural uranium mined out of the Earth,

19 melted down. You have a block of natural uranium with

20 all of the daughter products that have been building

21 in since time zero, --

22 MR. ESH: Yes.

23 VICE CHAIRMAN ARMIJO: -- billions of

24 years maybe, and the same block of depleted uranium.

25 You're telling me one block is 1,000 times more
133

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 hazardous or not?

2 MR. ESH: No, no, no. I'm saying that --

3 VICE CHAIRMAN ARMIJO: Go ahead. You're

4 the --

5 MR. ESH: I don't want to talk over

6 anybody else.

7 VICE CHAIRMAN ARMIJO: That's okay.

8 MR. ESH: Yes. If you take natural

9 uranium and you concentrate it until it is basically

10 pure --

11 VICE CHAIRMAN ARMIJO: And I'm talking

12 about you just take -- you go to the mill. You dig

13 up. You get uranium.

14 MR. ESH: Yes.

15 VICE CHAIRMAN ARMIJO: You haven't done

16 any purification. And you create a chunk of uranium

17 with all the daughter products that have been growing

18 in from time immemorial. And you compare that with a

19 chunk of depleted uranium that has gone through the

20 enrichment process and been purified and everything

21 else. You know, are you telling me that one of them

22 is inherently much more hazardous?

23 MR. ESH: If the natural uranium is

24 concentrated to 80 percent uranium, then the natural

25 uranium would be much more hazardous than the depleted
134

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 uranium at that time because the depleted uranium

2 doesn't have all the daughters in it yet.

3 If the natural uranium is clean of the

4 daughters and it's not concentrated, then the depleted

5 uranium has a higher concentration. It's much higher.

6 So the number that I was giving, about a factor of

7 1,000, is the depleted uranium is very concentrated in

8 uranium but very low in daughters. And those

9 daughters build in over time. It's about a factor of

10 1,000 lower at year 1,000 compared to year 1 million

11 or 2 million, so comparing depleted uranium to

12 depleted uranium at different times. That's the

13 comparison.

14 MEMBER RYAN: I understand those

15 equilibrium discussions. I think the other part of it

16 to me is benefit is it also has to then fit into what

17 is a scenario of exposure, which is a pathway to human

18 beings in some scenario of exposure. And that can be

19 a very complicated range of what is in play and what

20 is not.

21 MR. ESH: Yes. And I'll talk about

22 scenarios here in the guidance, especially for the

23 intruder component, but then you also have --

24 MEMBER RYAN: It's not just the inventory

25 that drives the bus.
135

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. ESH: Well, no, it's not. I mean, in

2 the performance assessment, it's inventory. It's

3 hopefully your design and your site and also then your

4 receptor scenarios and their characteristics. It's

5 all of those things put together that give you the

6 impacts that --

7 MEMBER RYAN: And go over institutional

8 controls if they are there and all of those things?

9 MR. ESH: Yes. But if you want to talk

10 just about the material, then make it relative to all

11 of those things put on a normalized basis. And then

12 you can just talk about the material characteristics.

13 Of course, if you're valuing the same

14 scenario at those two points in time, then the

15 comparison is valid. If you're evaluating different

16 scenarios at those two points in time, then the

17 ingrowth characteristics of a material may be worse or

18 less by the changes in the scenarios that you apply at

19 those different points in time.

20 MEMBER RYAN: So I think it's fair to say

21 there's no real three-sentence way to summarize what's

22 the risk from DU without considering all of these

23 different factors in context of how you really can

24 come up with a risk scenario for any given specific --

25 MR. ESH: The way the depleted uranium is
136

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 similar to other sorts of things, it's not different

2 in that it represents long-lived waste. And so what

3 do you do with long-lived waste, especially long-lived

4 waste in near-surface disposal.

5 The NRC when it developed the regulations

6 in the early 1980s, they put limits on the long-lived

7 waste that they thought were appropriate for

8 near-surface disposal. Those are reflected in the

9 61.55 tables.

10 So this idea of applying analysis right

11 now to determine on a site-specific basis how you

12 should limit maybe long-lived waste is no different.

13 It is consistent with what was done to develop the

14 regulation. It's only we're allowing the licensees to

15 do it on a site-specific basis, instead of the NRC

16 doing it on a predetermined humid site, humid

17 Southeastern site, and applying those results to all

18 sites throughout the country.

19 I think this approach is consistent, but

20 it's more risk-informed. But I would argue and I do

21 argue that you have to set requirements that allow you

22 to distinguish between an appropriate action and an

23 inappropriate action. And if you don't have a long

24 enough period of performance or you don't have some

25 evaluation of possible disturbance, then I think that
137

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 some materials that right now from a government policy

2 perspective they view as unsuitable for near-surface

3 disposal could meet those requirements.

4 So that tells me you need to set the

5 requirements where those materials couldn't meet and

6 other materials could meet it. That tells you when

7 you're at the right place of managing the waste. And

8 that's what we had attempted to do here.

9 For the post-20,000 years, we feel that

10 the impacts can be better placed in the proper context

11 in something like an environmental analysis. So we do

12 require, would require, that somebody generate a dose

13 number, but that is only to ensure transparency with

14 the stakeholders. At this time we weren't implying

15 regulatory requirements for that.

16 MEMBER CORRADINI: You've gone way beyond

17 my understanding something, but if I understand the

18 post and within, the 500 millirem and, as you said,

19 the consistency with the table -- I don't remember the

20 reference -- is within the 20,000 years.

21 MR. ESH: Yes.

22 MEMBER CORRADINI: And the post-20,000

23 years, if somebody were to put in a performance curve

24 that showed everything was hunky-dory within 500

25 millirem and then at 30,000 years or 40,000 years in
138

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 the simulation, it went from 100 millirem to a rem,

2 I'm trying to understand what that does to you.

3 That's just purely qualitative observation?

4 MR. ESH: Yes. That would not fail these

5 requirements as we have proposed them right now.

6 MEMBER CORRADINI: Okay.

7 MR. ESH: You would take that information.

8 In our case, we would evaluate it in our environmental

9 analysis and see whether that analysis was too large

10 and unjustified based on the action that wants to be

11 taken.

12 MEMBER CORRADINI: It's more qualitative.

13 You post this time period.

14 MR. ESH: Yes. If we have EIS people in

15 the room, they will be offended, but EIS analyses I

16 think are softer than the performance assessment type

17 of analyses.

18 MEMBER CORRADINI: Right.

19 MR. ESH: We're trying to make sure that

20 because you do have these vast uncertainties,

21 especially over the long time frames and so this is --

22 but we have had stakeholders comment each way. Some

23 feel that absolutely we should apply a dose limit at

24 those longer times. And they have recommended values,

25 100 millirem, 500 millirem, 25 millirem. We should
139

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 apply a dose limit regardless of the time. And then

2 we have had others say, "You shouldn't apply any dose

3 limit or require any analysis at that point in time."

4 MEMBER CORRADINI: That's fine. You

5 helped. You helped. Thank you very much.

6 MR. ESH: 

7 Next slide, please. The guidance document

8 we talked about pretty in-depth in the Subcommittee.

9 What this guidance document is is it provides guidance

10 on conducting site-specific analysis to demonstrate

11 compliance with the performance objectives.

12 We supplement existing low-level waste

13 guidance. So it isn't a standard-alone guidance

14 document. And the reason for that is primarily

15 because this is a limited-scope rulemaking.

16 In a comprehensive rulemaking, we would

17 maybe want to do something like we did in the

18 decommissioning program and make a consolidated

19 guidance document. That is a very big effort

20 involving a lot of people because there is a lot of

21 guidance, either direct or it may be ancillary, the

22 technical guidance and NUREGs and those sorts of

23 things. It can all be pulled together into one set of

24 guidance that you would maybe use for this program.

25 So what we did is we supplemented
140

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 guidance. We filled in holes that we thought we had

2 holes. We especially put detailed guidance into apply

3 to what we feel is risk-informed the way that you

4 would implement these regulatory requirements we are

5 proposing.

6 The Commission directed us to propose

7 parameters and assumptions to be used in the analyses.

8 We took some liberty -- and hopefully they're in

9 agreement with us -- that they didn't specifically

list the hydraulic conductivity should be 1E-7 10 meters

11 per second and the distribution coefficient for

12 technetium should be one milliliter per gram.

13 We didn't specify particular parameter

14 values. We talked technically about the parameter

15 values and assumptions and gave some examples about

16 uncertainty and variability that we wanted people to

17 consider in choosing the value for this one and say

18 further site-specific application.

19 And we can afford some flexibility where

20 warranted. In some cases, we don't think flexibility

21 is warranted, but we provide flexibility where we

22 think it is warranted.

23 Next slide, please. So the main outline,

24 we have an introduction, general technical analyses.

25 So that provides some discussion of things like data
141

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 uncertainty, model uncertainty, model support,

2 integration, abstraction, kind of the basic technical

3 building blocks that comprise a performance assessment

4 in these technical evaluations.

5 And then we cover what are more process

6 model-type things in performance assessment, such as

7 inventory and source term release and waste containers

8 and radionuclide transport biosphere modeling. All

9 those sorts of things we discuss in the performance

10 assessment modeling section.

11 That's an area where we felt we had some

12 pretty good guidance in like NUREG-1573 and a few

13 other documents. So we didn't go into great detail,

14 but we provided details we thought might be needed to

15 fill in some issues.

16 We did generate new guidance on the

17 intruder assessment, intruder dose assessment I should

18 say, because it wasn't required before. And we

19 thought there might be a need for some pretty good

20 guidance on that topic. So we have a pretty thick

21 section on intruder assessments. And I will cover

22 some of the elements as some examples to you in a few

23 slides here.

24 We have a section on long-term analyses,

25 the type of analyses we would expect somebody to
142

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 produce that justify what they would do to compare to

2 the 61.13(e) requirement; and then other

3 considerations, which are like developing inventory

4 limits, how you would go about that, how and why you

5 might develop inventory limits.

6 And, then, finally we have a performance

7 confirmation section and the use of other NRC guidance

8 documents.

9 Next slide, please. So we have some

10 guidance on period of performance. And what it

11 basically discusses is the flexibility that can be

12 afforded for short-lived waste or low concentrations

13 of long-lived waste. And what we are advocating is

14 that the primary differences are in the level of

15 detail of the justification for the calculations.

16 We also provide expectations for what you

17 would need to do for long-term analyses. So if we

18 could go to the next slide, I'll show you an example.

19 There are some example boxes right in the

20 guidance document to kind of pose questions and

21 answers that we think people might have when they're

22 doing the evaluation. And this example says, "Okay.

23 I have a facility that only has low-level waste

24 generated by commercial entities," which normally has

25 limited concentrations of long-lived waste. The
143

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 values of the waste are at or below one-tenth of the

2 table values.

3 Additionally, the facility is expected to

4 receive waste that is long-lived that are found in the

5 table that is less than the soil surrounding the

6 facility.

7 So in this case we say, "Okay. We need to

8 do the performance assessment to meet the 61.41, .42,

9 and .44-type requirements, but we don't have to get

10 into all the complicated business with what's

11 happening with climate and stability and all the

12 things that come into play over the very long-term

13 assessment period."

14 The reason why we have taken the approach

15 to the period of performance on the intruder

16 requirements in the regulations is legally you have to

17 set the requirements as to what you want to be met.

18 And then you can provide ability to demonstrate that

19 in a risk-informed way, which is generally done with

20 level of detail.

21 So you have to show that you have captured

22 the peaking of dose within 20,000 years, but you could

23 do that a number of ways. If I was doing it and I had

24 a facility that was only taking short-lived waste, I

25 would probably make an argument based on the
144

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 characteristics of the waste I had and show that it's

2 going to be all decayed by year whatever.

3 I also would consider just running the

4 calculation out and showing I did a bunch of zeroes at

5 longer times. That would be an easy, practical way to

6 do it because once you have set up the performance

7 assessment calculation, there is not a burden to

8 running the calculation longer. The burden comes in

9 as if you have to develop specialized models of what

10 is happening at longer time and provide support for

11 those calculations. And that is the way we think the

12 process should work.

13 If you're dealing with a hard problem,

14 you're going to be faced with a more challenging

15 review and more information that you're going to need

16 to supply. If you have an easy problem, you should be

17 able to deal with it in a more straightforward way.

18 MEMBER RYAN: Just a question, David, on

19 the example 2.3. What if I have some not small but

20 not horrendous quantity of uranium and I say, "Okay.

21 Well, I'm going to make that so that it's about the

22 same as resting in the natural soils in the

23 surrounding facility by mixing it with a whole bunch

24 of dirt"? What do you make of that?

25 I mean, I don't think it's all that -- I'd
145

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 much rather have one container that's at a robust

2 container buried 50 feet down than meet that goal.

3 MR. ESH: Yes. We did a blending

4 requirement or we have requirements about basically

5 dilution. So you can mix waste streams --

6 MEMBER RYAN: Yes.

7 MR. ESH: -- in order to manage the

8 disposal of those waste streams, say, by mixing a

9 class B waste with an A waste and get it all down to

10 A waste.

11 MEMBER RYAN: I mean, the point is that --

12 MR. ESH: You can do what you need to do

13 under the technical position on concentration

14 averaging to stabilize your material and take action

15 such as that, but you can't artificially dilute your

16 material by, say, mixing clean soil in with waste.

17 MEMBER RYAN: So it's all in the matter of

18 definition. If I'm blending waste for the purpose of

19 stabilizing what I have, which I could be doing with

20 a chunky uranium and other kinds of soil waste that

21 have a little bit of cobalt or whatever, okay.

22 MR. ESH: I think it's --

23 MEMBER RYAN: You try and judge intent

24 there, which is very interesting to think about how

25 that happens.
146

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. ESH: That's existing in the

2 regulation right now that you can do things to manage

3 your waste streams. But generally you can't -- I

4 mean, if the philosophy is concentrated and contained,

5 they don't want you doing dilution. Dilution is not

6 the solution to pollution, even though from a risk

7 analyst perspective, it is in many cases. You are

8 most confident that the risk is low when it is

9 diluted.

10 And that's what happens in these

11 performance assessments many of the time is that you

12 are trying to assess how much dilution and dispersion

13 you get out of the system. That's a --

14 MEMBER RYAN: These longstanding

15 principles may be right or may be inappropriate or not

16 useful.

17 MR. ESH: It may be, but that's not for us

18 to do within especially this rulemaking and maybe not

19 even within the comprehensive one. We can discuss it,

20 but those were decisions for Commission policy to set

21 how they want to manage waste, how they want to set

22 waste disposal and the framework for it.

23 MEMBER RYAN: I guess it's my view and

24 I'll express it for the rest of the members. I think

25 you're hamstrung by the fact that you are in a very
147

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 limited rulemaking circumstance right now. I think

2 that is something that we need to think about. This

3 is very limiting to what we can or can't do to try and

4 move the ball in a positive direction.

5 MR. ESH: I mean, this is brain surgery,

6 but it's not lobotomy. So, I mean, I think we are

7 delving in and working on the part that we need to

8 work on, but we aren't taking a dramatic action in how

9 we're trying to change the system because --

10 MEMBER RYAN: But you are only given a

11 vice grip and a screwdriver --

12 MR. ESH: Would have given us a hammer

13 when we needed a screwdriver, but so be it. And we

14 have had those comments from stakeholders that have

15 said, "Look, the system works. Don't break it."

16 We're certainly not trying to break it, but we have

17 been given direction to change it to deal with

18 specific waste streams and problems. And that's what

19 I think we did.

20 Let's talk about the intruders now. I

21 think that would be useful for you. The guidance on

22 the inadvertent intruder assessment, as you are

23 well-aware, most of you, probably boils down to

24 scenarios.

25 What our guidance says is that we want to
148

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 evaluate or want people to evaluate reasonably

2 foreseeable scenarios resulting in the greatest dose

3 for compliance. You can consider site information.

4 You are going to have flexibility to identify what the

5 reasonable foreseeable scenarios may be in the

6 near-term.

7 For longer time frames, you get into this

8 issue, though, of future human behavior. In those

9 cases, what we are recommending is, just to keep it

10 simple for yourself, it made you look at the default

11 scenarios.

12 The default scenarios limit speculation.

13 We can argue they are conservative, how conservative

14 they may be. They have a rich history of use in

15 practice, both from within the NRC and in some sites

16 that have done intruder evaluations. They are usually

17 looking at default scenarios. So there is a basis or

18 there is a history of usage for the default scenarios

19 at least.

20 If we go to the next slide, I'll show you

21 some more details on this. The default scenarios that

22 were considered, just to refresh your memory, they

23 were in intruder construction, discovery scenario.

24 You have the issue of whether waste is

25 recognizable or not. If the waste is recognizable
149

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 when the construction occurs, then they stop

2 construction. And the exposure time is much more

3 limited. If the waste is unrecognizable when the

4 construction occurs, then they build a house and

5 somebody lives there. And the exposure times are much

6 longer, and the pathways are much more involved.

7 For deeper waste, then, you may also need

8 to consider drilling. So somebody puts in a well, for

9 agricultural or domestic use, and look at the impacts

10 to the crew that puts in the well or the impacts to

11 somebody that lives and uses the water from the well

12 after it has been put in.

13 They are all hypothetical regulatory

14 constructs. They aren't meant to be "This is exactly

15 what we think would happen." But we do believe they

16 provide reasonable bounds to do a regulatory analysis

17 and they limit speculation about human activities

18 because when you talk with stakeholders about human

19 activities, their views are way more diverse than they

20 are about even something like period of performance.

21 Somebody can come up with very complicated

22 scenarios that they can justify "Well, my Uncle Joe

23 does this exact thing. Therefore, you should evaluate

24 it" without the context of "Well, not everybody has an

25 Uncle Joe that's crazy."
150

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 So this limits speculation about the human

2 activities, and I think it's appropriate. It may not

3 be appropriate at all sites, though. You need to

4 consider what's happening out at a particular site.

5 So if we go to the next slide, please --

6 VICE CHAIRMAN ARMIJO: David, just before

7 you go --

8 MR. ESH: Yes?

9 VICE CHAIRMAN ARMIJO: -- in your default

10 scenarios, do you specify the number of people who

11 were involved in this intrusion? Is there a maximum

12 number?

13 MR. ESH: It does not specify the number,

14 but it's generally thought to be, say, one family or

15 one residence. It's not a whole community, for

16 instance. The evaluation is not that a town gets

17 built but that a house gets built, which we think is

18 much more consistent with the idea that you are trying

19 to put controls in place to prevent something from

20 happening. And if something bad happens, it is likely

21 to be more limited to an extent than comprehensive.

22 Maybe that's not a good assumption, but that's that

23 assumption to --

24 VICE CHAIRMAN ARMIJO: Okay. I just

25 wanted to know what the number was.
151

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER BROWN: It just hit me based on

2 what you said. So construction people coming in, this

3 assumes, then, that these are not barriered sites.

4 These are open field after the disposal has been done.

5 Is that after some period of time or is that --

6 MR. ESH: Yes.

7 MEMBER BROWN: Is it 100 years? It is 10

8 years or is it the 10,000-year point?

9 MR. ESH: It's after the institutional

10 control period, which is up to 100 years. So it's

11 after that time. During that time, there are active

12 controls, like fences and security and --

13 MEMBER BROWN: The factory gets torn down.

14 And then the fences go away and the --

15 MR. ESH: Yes. And you can imagine if --

16 well, the other thing is, say, for instance, if you're

17 dealing with companies, how many companies in the S&P

18 500 are 100 years old? It's only a handful of them

19 that are that old. We start dealing with companies

20 that come and go over long time periods.

21 MEMBER RYAN: David, I'm not trying to

22 rush you, but I want you to maybe move along a little

23 bit.

24 MR. ESH: Yes.

25 MEMBER RYAN: I think we have covered this
152

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 one point.

2 MR. ESH: All right. Fine.

3 MEMBER RYAN: We need to keep going.

4 MR. ESH: All right. So the next slide,

5 then, is the site-specific scenarios. This is the

6 other aspect that we're bringing into play in the

7 intruder assessment is we want people to be smart

8 about it.

9 So, Dr. Ryan, you talked a lot about

10 "Well, does it make sense to assume that somebody

11 builds a house and they are eating a steam generator"

12 or whatever, you know, some sort of metallic component

13 that is obviously still metallic at 100 years? No,

14 that doesn't make sense at all.

15 Sure, you can do it for your regulatory

16 analysis if you want to be conservative and you show

17 you can meet the requirements. Why not? But you

18 don't have to do that.

19 MEMBER RYAN: I sure wouldn't do it.

20 MR. ESH: You can make an argument that,

21 "Look, this waste is recognizable. So my scenario is

22 limited to scenarios that would happen when the waste

23 is recognizable."

24 So we feel that we allow people to bring

25 in the physical information and then also cultural
153

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 information. So if a waste disposal facility is

2 located in an industrial area and it's been an

3 industrial area for some time, it's likely for, at

4 least the immediate future, to remain an industrial

5 area. Maybe you can look at industrial-type

6 scenarios, instead of a residential-type scenario,

7 after the institutional control period.

8 But the ability to do that over very long

9 periods of time starts getting limited. So we do ask

10 for people to consider changes over time, either to

11 the physical information, like maybe you have waste

12 that's not potable today you need to look at "Is that

13 a robust configuration? Does it remain unpotable?"

14 MEMBER RYAN: Just as another example, I

15 think our previous conversations touched on the depth

16 of burial.

17 MR. ESH: Yes.

18 MEMBER RYAN: If I'm at a site where I can

19 go, let's say, 100 feet down, houses aren't going to

20 put basements 10 stories down.

21 MR. ESH: Absolutely no.

22 MEMBER RYAN: I think there's a way to

23 think about, "Well, how do I get it out of reach of

24 the intruder? And if my site allows that, bingo."

25 And I think that's a positive way to move forward.
154

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. ESH: Well, that is a very good way to

2 try to reduce the likelihood of interaction with the

3 material and disturbance of the material by natural

4 processes. That's why high-level waste is desired to

5 go in a geologic repository, to eliminate the

6 instability associated with the near surface and the

7 potential human interaction.

8 So it's a concept that is applied

9 universally worldwide. The further you can isolate

10 the material from the people and the environment, the

11 better off you will be over these long --

12 VICE CHAIRMAN ARMIJO: You can't get away

13 from the imagination of the assessors. I recall a

14 Department of Energy document that I saw on Yucca

15 Mountain where the intruder was drilling 1,000 feet

16 down through Yucca Mountain, through the drip shield,

17 through the waste packages, and into the fuel, and, of

18 course, exposed, causing exposure and release.

19 I mean, so these are open-ended. You can

20 go in these fine frames and open strengths. You just

21 can't close on the problem.

22 MR. ESH: That's why, especially in this

23 area, we want to kind of constrain speculation and

24 limit speculation to a few scenarios that have been

25 used in the past or to consider that this type of
155

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 information on slide 20 that we have right here,

2 especially in the short term, to be smart about it

3 because for short-lived waste, these sorts of

4 considerations can make a very big difference.

5 The long-lived waste, we think they make

6 lots of a difference. So when you're in the

7 long-lived waste box, then you probably want to be

8 more simple and pragmatic about the uncertainties and

9 the solution and you try to mitigate those

10 uncertainties.

11 MEMBER RYAN: And I guess it would be

12 helpful if, at least in guidance, if not in the

13 regulation changes you are proposing themselves, we

14 address this very point that Dr. Armijo and you just

15 talked about.

16 MR. ESH: I believe it is. I mean, we

17 would love your feedback on that guidance document, on

18 this guidance document. The intention is that it's

19 going to go out for public comment with the proposed

20 rule, we'll get feedback on it.

21 MEMBER RYAN: We haven't seen it yet. So

22 --

23 MR. ESH: Yes. I would say it's like 95

24 percent there, maybe even 99 percent there. It's

25 getting pretty close.
156

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER RYAN: Okay. Well, we would be

2 happy to schedule a briefing whenever you are ready.

3 MR. ESH: Yes. Next slide, please. So

4 conclusions, and I'll pass off to Andrew to go over

5 public comments quickly. We feel we followed and

6 addressed the Commission direction, the proposing

7 rulemaking, limited rulemaking to site-specific

8 analyses.

9 We do identify what requirements we

10 believe should be associated with those analyses. And

11 we have developed a guidance document outlining the

12 key parameters and assumptions and all the technical

13 information to go with the analyses.

14 The approach we believe is protective of

15 public health and safety, it is risk-informed and

16 performance-based. And we do provide flexibility to

17 licensees when warranted.

18 So Andrew?

19 MR. CARRERA: Thank you, Dave.

20 My name is Andrew Carrera. And for the

21 next couple of slides, I will just briefly go through

22 the comments that we received on this rulemaking, go

23 through the language and how the working group came

24 out of pursuing those comments. And then we still go

25 back to Dr. Armijo's questions with regards to the
157

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Department of Energy's comments. And then I'll

2 proceed with the path forward.

3 So the NRC posted the proposed rule on

4 regulations.gov and requested early public comments.

5 And we also had a public meeting on May 18th to

6 discuss this document.

7 The comment period ended on June 18th. We

8 also heard some of the comments from stakeholders

9 during the previous meeting.

10 And at the end of the comment period after

11 the staff reviewed 15 comment letters from this group

12 of stakeholders, industry, government organization,

13 and grouped them into these 9 issues. And Dave has

14 previously talked about these issues in the comments

15 regarding these issues already.

16 In the end, the working group sees

17 comments as being both supportive and critical for

18 what we are proposing in the formal proposed rule

19 language. And in the areas where we see the comments

20 leaning one way or the other, we went back to the

21 preliminary proposed rule language and made revisions

22 to address those issues.

23 Those revisions are included in the

24 background slides. I don't know if you want to go

25 over that now.
158

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 The working group is comfortable with the

2 direction that the revision is taking us. And we are

3 comfortable with the current path that we are on with

4 the rulemaking.

5 Stakeholders will have another chance to

6 comment on the proposed rule language when it goes out

7 officially for an official comment period on the

8 proposed rule.

9 MEMBER RYAN: When do you think that will

10 be released for comment, just roughly? Is it this

11 year or first of next year?

12 MR. CARRERA: It would be next year.

13 MEMBER RYAN: Okay.

14 MR. CARRERA: The package, the first

15 review package, is scheduled to be delivered to the

16 Commission at the end of January 2012.

17 MEMBER RYAN: Okay.

18 MR. CARRERA: And then the Commission will

19 review and vote on it. And I don't know how long that

20 process will take.

21 MEMBER RYAN: Okay.

22 VICE CHAIRMAN ARMIJO: Yes. I'd like to

23 make a comment that I had hoped you would provide more

24 detail on the Department of Energy comments because I

25 thought they submitted very detailed and
159

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 well-thought-out comments.

2 You know, I won't go into all of their

3 reasoning and everything they said, but basically they

4 wind up with a period of performance of 1,000 years.

5 MR. CARRERA: Yes.

6 VICE CHAIRMAN ARMIJO: They address the

7 issue of intruders with some constraints. Reasonable

8 people will behave in the future pretty much like they

9 behave today. And they come up with something that

10 looks practical and workable. And 1,000 years is far

11 different than a 20,000-year assessment and certainly

12 easier to believe that you understand what is going on

13 as far as materials, environment, and even people.

14 You know, the country may not exist in 1,000 years,

15 but let's hope they do, we do.

16 I can't reconcile two government agencies,

17 responsible agencies, Department of Energy already

18 disposing of low-level waste, including depleted

19 uranium, and NRC regulating the disposal of the same

20 materials, having two radically different conclusions

21 on periods of performance and how you do intruder

22 assessment and whether -- so I just think that this

23 has got to get resolved.

24 And once the -- you know, I can understand

25 the DOE approach much better. And I could believe
160

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 that they can support their arguments for 1,000 years.

2 MR. ESH: I can talk to that. We work

3 with the Department of Energy on a number of projects,

4 especially down to processing reviews. And in those

5 projects, they don't use 1,000 years. They use 10,000

6 years, and they look beyond 10,000 years. So when

7 you're looking at the 1,000 years, you're looking at

8 the requirements in order 435.1 that they're applying

9 for maybe what they call their low-level waste

10 disposal facilities, where I believe they limit --

11 they develop waste acceptance criteria but they limit

12 the concentrations of all long-lived isotopes that

13 they take in those facilities, as they need to on a

14 site-specific basis.

15 Let me talk about intruder area first. In

16 the intruder area, I don't think we're in misalignment

17 with what the Department of Energy does. They do an

18 intruder assessment. They look at what they think are

19 reasonable scenarios. We may differ as you go out in

20 time how much we think the relevance of -- how much

21 recency bias comes into play. So they believe because

22 the Department of Energy is there now that it's always

23 going to be there. And if it's an industrial-type

24 activity now, then they can use an industrial-type

25 activity indefinitely into the future in some cases.
161

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 In other cases and problems that we

2 review, they don't take that approach. They analyze

3 an intruder very similar to what we would do, but they

4 apply a 100-millirem dose limit, instead of 500.

5 That's one of the main differences.

6 And they separate it into a chronic and

7 acute case. They look at acute exposures and chronic

8 exposures and make a distinction between them. So

9 we're not in misalignment in the intruder area.

10 In the area of the period of performance,

11 where they choose 1,000 years, I'm not aware of the

12 basis for or the document that describes why they came

13 up with the 1,000 years. Basically they have 1,000

14 years, and they have used it. And in the material

15 they submitted to us or the comments that they made at

16 our public meeting, it was basically, "Well, we have

17 used 1,000 years for a long time," but they don't say

18 why they picked 1,000 years or why it's appropriate

19 for the problem.

20 And I would argue for the direction the

21 Commission gave us, especially for depleted uranium,

22 1,000 years is not appropriate. It just does not

23 capture enough of the characteristics of the material.

24 You are way off on the ingrowth characteristics of the

25 material to make an argument along those lines.
162

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 If you have some sort of socioeconomic

2 argument about what is going on in society in the

3 future in evolution and technology to justify a

4 shorter period of performance and how other societies

5 should deal with the long-term risk, that's a

6 different story, but we don't have that analysis. And

7 I'm not aware that the Department of Energy has that

8 analysis.

9 And in practice, when we do the reviews,

10 independent reviews, of what the Department of Energy

11 does, they project impacts, say, even past 10,000

12 years, but they, to our knowledge, don't take them

13 seriously or take any action on it.

14 So it's a little bit disingenuous to say,

15 "Yes. We have some line in the sand that we draw at

16 1,000, but then we also consider what is going on

17 after that" because in practice, when we are doing our

18 independent reviews, they aren't taking action on what

19 is going on after that. They are just drawing the

20 line in the sand and saying, "That is where we draw

21 it."

22 And I don't think you can draw it there

23 both from a depleted uranium radiological

24 characteristic standpoint or from a radiological

25 transport characteristic for most of these problems
163

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 because you're dealing with a situation where an

2 isotope does not get out in 1,000 years but may arrive

3 in 1,500.

4 And you might have zero dose for 1,000

5 years and 5 rem at year 1,500. But that doesn't make

6 any sense that just because where you wanted to draw

7 the regulatory requirement, it's a dramatic pass or a

8 dramatic fail.

9 So that's kind of my thoughts on it. I do

10 realize we have some differences there. But we tried

11 to develop a technical basis for it. And considering

12 what we see in practice of the way they do it, we

13 understand exactly how they run their problems and how

14 they do their analyses. We don't necessarily agree

15 with them, obviously.

16 VICE CHAIRMAN ARMIJO: Well, you know,

17 it's clear that they're different. They are

18 different. You say that you don't have a basis or

19 they haven't shared their basis for their 1,000 years.

20 They did share their documents on what

21 their rules are and their processes are. And they

22 address the intruder assessment and, for whatever

23 reason, think 1,000 years reasonable and practical.

24 And that's where they draw the line.

25 MR. ESH: Yes.
164

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 VICE CHAIRMAN ARMIJO: And I just can't

2 see the federal government having two agencies, both

3 responsible for disposing of the same thing, having

4 two different views.

5 One could argue and say, "Well, look.

6 We're going to be tougher on the private sector.

7 We're going to make them worry about stuff for 20,000

8 years. But the Department of Energy government

9 property, we just will do it for 1,000."

10 Something is wrong here. And I just find

11 it believable and practical that 1,000 years is plenty

12 of time, even though you can -- you know, I understand

13 your radiological arguments, but do we have a duty,

14 moral, ethical, legal, to protect a family 20,000

15 years out into the future? I don't believe so.

16 MR. ESH: That's the issue. It's like

17 "Well, what is the" --

18 MEMBER RYAN: We've probably --

19 VICE CHAIRMAN ARMIJO: I'm not talking --

20 MEMBER RYAN: Let others have a chance for

21 some questions.

22 VICE CHAIRMAN ARMIJO: Okay.

23 MEMBER RYAN: Okay. Jack? Okay. Dennis?

24 MEMBER BLEY: No more. Thanks.

25 MEMBER RYAN: Okay. Dana?
165

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER POWERS: I was at the Subcommittee

2 meeting.

3 MEMBER RYAN: Okay. Bill? Back to you.

4 VICE CHAIRMAN ARMIJO: I'm finished.

5 MR. ESH: One thing I would add is that

6 what I was trying to say is that we set the

7 requirement. So we think certain materials would pass

8 that we think are appropriate to pass. And other ones

9 that aren't appropriate wouldn't pass.

10 If you set a period of performance of

11 1,000 years and say, "Did away with the intruder

12 performance objective," I believe that defense

13 high-level waste would meet those criteria for

14 near-surface disposal and probably even commercial

15 spent nuclear fuel as long as you've got a shielding

16 barrier on top of it to take care of the high-activity

17 short-lived stuff. And that's a dramatic move from

18 the policy of the Commission right now as to how they

19 think you should manage certain materials.

20 So in my mind, the requirements have to be

21 able to distinguish -- it has to get the right

22 materials in the right boxes. And I think these

23 requirements do that.

24 MEMBER RYAN: One thing, David, I hope

25 you'll agree is that 19 -- I don't know whether it was
166

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 first written in '61, in the '70s -- the best

2 calculator you could was a card Wang calculator that

3 would do a really simple calculation in about a day.

4 MR. ESH: Yes.

5 MEMBER RYAN: And now we confuse ourselves

6 silly with a desktop portable computer and do

7 differential equations until the cows come home.

8 So the ability to calculate is so powerful

9 that I think we need -- my own view is this is --

10 performance assessment is a victim of "Well, let's

11 just calculate everything without really thinking it

12 doesn't make any sense."

13 I mean, so we can calculate impacts to any

14 species in between the waste and the cosmos. Because

15 we know where they are, we can run a differential

16 equation to do it. And I think sometimes we need to

17 think about what makes sense --

18 MR. ESH: Yes.

19 MEMBER RYAN: -- to do. I mean, where are

20 the limits of this? I think Dr. Armijo is trying to

21 address in his mind a very important point about where

22 are the limits of where these calculations make sense

23 or can we defend it? And it gets into the

24 uncertainty.

25 It's not uncertainty analysis of the
167

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 parametric uncertainty.

2 MR. ESH: Yes. I understand that, yes.

3 MEMBER RYAN: It's the uncertainty and

4 what do we know or don't we know. So I think that's

5 part of what you're hearing a little bit from the

6 Committee. And during the Subcommittee meetings, we

7 have touched on this.

8 So, with that, I don't think we have any

9 other questions. I'll go around once more. Anybody

10 else have any questions or comments?

11 (No response.)

12 MEMBER RYAN: I do want to thank David and

13 Andrew and Debbie for not only supporting this meeting

14 but for the two very detailed and very productive

15 Subcommittee meetings that we had with other

16 participants.

17 I want to thank the other staff from the

18 Low-Level Waste Branch that are here in the audience

19 who are, as I said many times, probably the most

20 talented group of folks in performance assessment I

21 have seen put together in one group. And I appreciate

22 your time. And so I thank you all for coming and for

23 being here and for your participation.

24 Are there any other comments from members

25 of the public?
168

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER POWERS: I would just echo your

2 comment. The presentation at the Subcommittee meeting

3 was a tour de force, very professional, well-done.

4 MEMBER RYAN: Thank you, Dr. Powers.

5 Is there anybody on the bridge line who

6 wishes to make a comment?

7 (No response.)

8 MEMBER RYAN: So if the bridge line is not

9 closed, we can close it now. With that, Mr. Chairman,

10 I will turn the meeting back to you. Thank you.

11 CHAIRMAN ABDEL-KHALIK: Thank you.

12 Before we break for lunch, I would like to

13 welcome our newest member. Gordon Skillman is now an

14 official member of ACRS. And we welcome him.

15 MEMBER SKILLMAN: Thank you very much.

16 (Applause.)

17 CHAIRMAN ABDEL-KHALIK: Let me just give

18 you a brief bio on Mr. Skillman. Mr. Skillman has

19 over 45 years of commercial nuclear power experience.

20 He has served on nuclear safety oversight boards and

21 engineering councils for many years and has been

22 directly involved in design consultation or oversight

23 actions at many of the currently operating plants in

24 the United States.

25 Mr. Skillman earned his reactor operator's
169

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 license and senior reactor operator's license from the

2 U.S. Atomic Energy Commission in 1967 and 1969 and

3 served on the nuclear merchant ship NS Savannah as a

4 reactor operator.

5 He later joined the Babcock and Wilcox

6 Company, where he contributed as an engineer and

7 manager for B&W's Nuclear Power Generation Division.

8 He was an immediate responder to the TMI

9 2 accident and served for seven years on the

10 stabilization and cleanup of TMI 2 from GPU Nuclear.

11 Mr. Skillman subsequently served as Manager of

12 Recovery Support Engineering and Manager of Defueling

13 for TMI 2.

14 Following his employment with GPU, Mr.

15 Skillman has provided consultation and oversight

16 services to the nuclear industry. In his consulting

17 capacity, he has been involved in a variety of

18 activities, including the response to the Davis-Besse

19 head event and design and construction of the national

20 enrichment facility at Hobbs, New Mexico.

21 Mr. Skillman received his Bachelor of

22 Science degree in marine engineering from the United

23 States Merchant Marine Academy in 1966. And he is a

24 registered Professional Engineer in Pennsylvania and

25 Virginia.
170

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Welcome aboard.

2 MEMBER SKILLMAN: Thank you.

3 CHAIRMAN ABDEL-KHALIK: Okay. Thank you.

4 At this time, we will take a break for

5 lunch. And we will reconvene at 1:15.

6 (Whereupon, a luncheon recess was taken

7 at 12:13 p.m.)

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25
171

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 A-F-T-E-R-N-O-O-N S-E-S-S-I-O-N

2 1:14 p.m.

3 CHAIRMAN ABDEL-KHALIK: We're back in

4 session.

5 At this time, we will move to the next

6 item on the agenda, Safety Evaluation Report

7 Associated with Revision 19 of the AP1000 Design

8 Control Document Amendment. And Mr. Ray will lead us

9 through that discussion.

10 Harold?

11 MEMBER RAY: Thank you, Mr. Chairman.

12 As you just said, the agenda item is

13 entitled Safety Evaluation Report Associated with

14 Revision 19 but actually what exists is the final

15 Safety Evaluation Report. It's dated August 5th and

16 it includes Revision 19 to the AP1000 DCD Amendment.

17 The AP1000 Subcommittee met on August

18 16th, ten days following the issuance of the Final

19 Safety Evaluation Report for the entire amendment,

20 including Revision 19 to review the changes that were

21 made just by Revision 19 as we had, of course,

22 reviewed through Revision 18 at the end of last year.

23 This review was facilitated by the staff

24 providing us with an extract from the Final Safety

25 Evaluation Report, which addressed just the Revision
172

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 19 changes. I guess I'm not sure if the ACRS has

2 previously reviewed changes to an application after

3 issuance of the Final Safety Evaluation Report. But

4 in any case, that's what we're doing now.

5 Most, but not all, of the changes in

6 Revision 19, which had been submitted June 30th, 2011,

7 are editorial or conforming for the issues previously

8 identified by staff and which are now being closed

9 out. An example of such an item is the inclusion of

10 certain structural details in the enhanced shield

11 building as Tier 2*.

12 In regards to the enhanced shield building

13 structural design, there was a change made at NRC

14 staff request to combine extreme ambient thermal loads

15 in safe shutdown earthquake loads. Associated with

16 this change, the Subcommittee pursued at the August

17 16th meeting the effect of solar radiation in

18 potentially causing even higher loads. This is

19 referred to as the solar gain effect.

20 To explain a reason for including the

21 additional enhanced shield building structural detail

22 as Tier 2*, let me quote from the final draft rule,

23 which explains the reason for most of these revisions

24 to the DCD Revision 19.

25 "These revisions were to the DCD wording
173

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 about the design but were not actual design changes.

2 The purpose was to ensure that sufficient information

3 was continued in the DCD to provide a clear licensing

4 basis for the future and to ensure that key details

5 about structures, example materials, reinforcement

6 details, were subject to increased regulatory control

7 with Tier 2*.

8 "Because there are no consensus standards

9 applicable to the modules, the NRC concludes that some

10 information about this unique design warrants Tier 2*

11 regulatory controls."

12 The most challenging area for the

13 Subcommittee to resolve in the time since the FSER was

14 issued August 5th involves the various aspects of the

15 containment evaluation methodology. The most

16 important of these is the calculated peak accident

17 pressure. But this is not the only one.

18 As stated in the Draft Final Rule, the

19 design changes within the scope of the amendment with

20 respect to the containment vessel are the calculated

21 accident pressure to correct a number of errors, one

22 of which was identified in the ACRS letter dated

23 December 13th, 2010, and the balance of which were

24 identified by the Applicant and addressed in an update

25 to the shield building design report dated June 15th,
174

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 2011.

2 In response to a comment from a member of

3 the public, the Subcommittee has also sought to

4 determine if there is a nonconservative error in the

5 containment evaluation methodology associated with the

6 conduct of what is called the large scale test

7 initially performed in support of the AP600 design.

8 Such an error would be related to the effect of solar

9 heating of the facility, which was located outdoors.

10 At the August 16th Subcommittee meeting,

11 and in preparing for this full Committee meeting, I've

12 had been greatly assisted by Bill Shack and Sanjoy

13 Banerjee in their respective areas of expertise.

14 We've been asked to issue a letter on Revision 19 at

15 this full Committee meeting if at all possible.

16 Therefore, in the interest of time, I will ask that

17 Bill and Sanjoy lead with any questions they have in

18 their areas.

19 Finally, I want to note that I believe a

20 concern pursued by Sam Armijo regarding materials

21 testing related to the rad coolant pump flywheel has

22 fully resolved by the Applicant and is satisfactory.

23 Therefore, I would like to allocate most

24 of the time, to the extent that I can, to achieving

25 closure of matters related to the containment
175

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 evaluation methodology as the first priority for our

2 discussion. And with that, the agenda will -- we'll

3 proceed to follow the agenda, which involves

4 presentations by the Applicant. Over to your, Rolf.

5 MR. ZIESING: Okay. Thank you, Mr. Ray,

6 Chairman. Appreciate the opportunity of being here

7 today to address your questions.

8 In the interest of time, I think Mr. Ray

9 summarized what I was going to summarize. So I don't

10 want to repeat myself. We do have the slides. They

11 are provided for your information and for the record.

12 And we are prepared to focus on what we understand to

13 be the primary topics of interest, namely the internal

14 pressure and the questions on the structures.

15 We did have the structures folks lined up

16 here first, but if you'd like to talk internal

17 pressure, we'll get them.

18 MEMBER RAY: I put them first, too, Rolf,

19 but I will say you do whatever you think is best.

20 Both Bill and Sanjoy, I think, are prepared. So go

21 ahead as you planned.

22 MR. ZIESING: Okay. We'll stick to that.

23 So I really don't intend to go through

24 each of my slides in the interest of time. The

25 details will be covered in following presentations.
176

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 But I do have just an intro remark or two to make.

2 The DCD is today, for all practical

3 purposes, the same DCD that was subject to your prior

4 review only better. And I mean that seriously.

5 Since the time in which you completed your

6 review to Revision 18 and our issuance of Rev 19 and

7 the following issuance of the FSER, the Final Safety

8 Evaluation, we've been through an exhaustive review by

9 NRC following through on known confirmatory items.

10 Many inspections and audits to run the confirmatory

11 items to ground.

12 As a result of that thorough review, the

13 design was validated. Certainly there were some

14 analyses that changed and supporting information was

15 updated. But the design was validated through that

16 effort as documented with the issuance of the FSER.

17 And I said it is better. By that I mean

18 that at a high level, the design remains the same.

19 But I believe the document is improved in terms of

20 clarification. It is important that the licensing

21 basis, you know, be as clear as possible. And there

22 were edits made as a result of the confirmatory

23 reviews, the audits, inspections, and meetings that we

24 had, many of those were public, to ensure there was no

25 ambiguity around key licensing basis-type language.
177

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 And it was significantly strengthened from

2 a regulatory control standpoint with the

3 identification and addition of Tier 2* designation to

4 existing information or, in some cases, some

5 supplemental information such that future design

6 changes, you know, are more tightly controlled with

7 regard to the regulations that apply.

8 So it represents a design that has been

9 the subject of years of review. And the regulatory

10 basis, in my opinion, has been strengthened through

11 the confirmation review process and the inclusion of

12 Tier 2*.

13 So with that -- those are my intro

14 remarks. I do think it is important to preserve the

15 balance of time to get through the technical issues

16 and answer any questions you may have. So with that,

17 I'll turn it over -- we do have the Structures folks

18 lined up first. So we'll go ahead and address that

19 topic first. Mike?

20 MR. CORLETTI: Sure. Good afternoon. My

21 name is Mike Corletti. I'm Director of Engineering at

22 Westinghouse. With me we have Leo Tunon-Sanjur,

23 Structural Manager, and Tod Baker, Engineer in

24 Structurals area, who are going to be speaking today

25 with regards to the structural analysis changes that
178

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 are included in DCD 19, the differences between what

2 was in DCD 18 and what was in DCD 19.

3 The two key topics we're going to speak to

4 today is -- one is what we term the seismic and

5 thermal load combination issue. And included in that

6 are any responses to two questions that were raised in

7 our Subcommittee meeting, at the Subcommittee meeting

8 held three weeks ago, one associated with the welding

9 requirements, which I think at that meeting, I think

10 we answered the question -- read it into the record.

11 I think we have it our slide here,

12 specifically where the welding requirements are

13 captured in the certified design, in the DCD, or in

14 other topical reports that are referenced in the DCD.

15 The other topic under seismic and thermal

16 load combination we will speak to is the effect of

17 solar gang. There was a presentation made by a member

18 of the public last -- three weeks ago. We would like

19 to explain the effects of solar gain on the structure

20 and the importance of that. So -- and I think we have

21 a slide on that to speak to that question.

22 The second topic is with regards to the

23 PSC tank analysis that is presented in the DCD. And

24 there it really is the -- what was included in DCD 18.

25 And now what is now included describing that analysis
179

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 in DCD 19. Those are the topics we'll speak to.

2 First of all, with regards to the load

3 combination issue, the issue essentially is that for

4 ambient thermal conditions, when we do -- when

5 Westinghouse had performed the design in accordance

6 with ACI 349, we did not explicitly combine the loads

7 from ambient thermal with a seismic event. And that

8 is in line with, I think, a practice that has been

9 done by Westinghouse in the past and in other AEs that

10 have done nuclear structures design.

11 However, I think the staff basically had

12 asked us to quantify that effect -- really quantify

13 that engineering judgment. And Westinghouse has

14 performed a series of calculations that shows that

15 effect. And have included the results of those

16 calculations in the DCD Rev 19.

17 So next slide. Again, to validate the

18 existing shield building design, we updated those

19 calculations for not only the shield building but we

20 also included an update for all of the Nuclear Island

21 structures. As I said, this has been our past

22 practice for the ambient thermal that we did not

23 explicitly combine that. We really cited provisions

24 in the ACI Code that allowed that. However, we have

25 updated the calculations to explicitly include that
180

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 now.

2 The revised calculations really

3 demonstrate that there is not change in the structural

4 design. The amount of reinforcement, it has not

5 changed. And really, the effect with respect to the

6 margins is fairly small.

7 The DCD text changes were included in Rev

8 19 to really clarify the licensing basis. In the DCD,

9 we include details of load combinations for the

10 structures, including the critical sections. And the

11 staff, as part of the review under Part 52, does a

12 review of the critical sections.

13 And those methods that are applied for

14 those critical sections, then will be applied by

15 Westinghouse in the design of the entire structure.

16 So this really sets the licensing basis for the

17 calculations that will be done, the detailed

18 calculations that will be done for the Nuclear Island

19 structures.

20 MEMBER SHACK: Now when I looked at those

21 calculations, those were done basically with a kind of

22 effective -- those were done with the ANSIS model, not

23 the detailed one where you explicitly included the tie

24 rods and all the stuff and sort of following a

25 standard global.
181

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 But back in the earlier part of the shield

2 building report, there was a discussion of thermal

3 gradients within the composite. And there, there was

4 sort of a statement that it was modeled -- I think it

5 was not the seismic plus thermal but was thermal only

6 was modeled on a detailed basis.

7 I could find a quoting of the result,

8 which was that there was a 700 psi stress. And it

9 introduced a small amount of cracking, which is

10 addressed in the ACI by reducing to -- but I didn't

11 see those calculations explicitly in the shield

12 building report.

13 Are there in there somewhere? And then I

14 just missed them? For the localized thermal gradient

15 and the detailed result where you had the tie rods,

16 the steel --

17 PARTICIPANT: We can look.

18 MR. CORLETTI: But the results are

19 included in the shield building. I believe in our

20 seismic -- I don't believe -- in our seismic plus

21 thermal load combination calculations, they were

22 detailed in the last appendix.

23 So if you recall the previous version of

24 the shield building report, that load combination was

25 not included in the body of the report. We had
182

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 largely left the body of the report untouched. And

2 included in that last appendix the detailing of our

3 seismic plus thermal calculations.

4 MR. TUNON-SANJUR: But his question is

5 more for the localized thermal.

6 MR. CORLETTI: Oh, okay. Localized

7 thermal.

8 MEMBER SHACK: Yes, no, I certainly -- the

9 seismic plus thermal --

10 MR. TUNON-SANJUR: It exaggerated the

11 thermal gradient. So it is in the appendices, Chapter

12 3.

13 MEMBER SHACK: Okay. The result is in

14 Chapter 3. But I couldn't find any detail of the

15 analysis anywhere.

16 MR. TUNON-SANJUR: The description of the

17 analysis, there were calculations made.

18 MEMBER SHACK: So it was done with an

19 ANSIS modeling?

20 MR. TUNON-SANJUR: Yes. It was done with

21 actually an ABACUS model --

22 MEMBER SHACK: ABACUS, okay.

23 MR. TUNON-SANJUR: -- which captures the

24 leading aspect of the thermal. So the thermal

25 gradients were exaggerated. And so we came up with a
183

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 very steep thermal gradient, especially close to the

2 studs and the plate. And then ABACUS showed the

3 results to be about 700 psi.

4 MEMBER SHACK: Okay.

5 MR. CORLETTI: Yes, I think a lot of time

6 we present the results and I think the staff has done

7 audits of the calculations where maybe they would

8 review those audits. So I think the body of the calc

9 is not included in the report. Okay?

10 MEMBER SHACK: Yes, okay.

11 MR. CORLETTI: Okay. On this next slide,

12 there was a question at the Subcommittee with regards

13 to what are the shield building weld requirements.

14 And is it adequately captured in the licensing basis.

15 And the purpose of this slide really is to

16 -- I think we read this into the record at the last

17 meeting but really it is to identify that the weld

18 detailing requirements for the SHIELD BUILDING REPORT

19 structures do follow the AISC N690 code. And it is

20 specified in two documents.

21 And we mentioned that there was a

22 proprietary document that's referenced in the DCD,

23 APP-GW-GLR-602, which includes some of the details of

24 the shield building that the staff had believed was

25 the most important, that Westinghouse could not change
184

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 without coming back to the staff, that becomes

2 certified as part of the design. And so some of those

3 requirements are included in that document as well as

4 other portions of DCD Rev 19.

5 This slide really outlines in design in

6 the steel-to-steel and steel-to-concrete we'll follow

7 AISC N690 or the ACI 349 codes as appropriate. And

8 this really outlines some of the requirements that are

9 included in those two documents.

10 MEMBER SHACK: Okay. One requirement that

11 you did miss here is for the tie bar welds to the

12 plate, which again is a nonstandard kind of weld. And

13 you've addressed that by a performance requirement,

14 which seems to me adequate.

15 I did have a question -- and I don't know

16 whether this gets into proprietary information or not

17 -- you use mechanical couplers in some cases. And it

18 says those mechanical couplers -- and, again, those

19 mechanical couplers have a performance requirement,

20 which seems appropriate -- but it says they've been

21 used elsewhere. And I was just wondering where the

22 experience is in their use.

23 MR. TUNON-SANJUR: The mechanical couplers

24 are used sometimes for tying the rebars together.

25 MEMBER SHACK: Even in a standard
185

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 reinforced concrete structure.

2 MR. TUNON-SANJUR: Right. Even in

3 standard reinforced concrete.

4 MEMBER SHACK: Okay. So it's just a --

5 MR. TUNON-SANJUR: Yes.

6 MEMBER SHACK: -- it just adapted from the

7 conventional reinforced concrete structure?

8 MR. TUNON-SANJUR: That's correct.

9 MEMBER SHACK: Okay.

10 MR. CORLETTI: Next slide. So this next

11 slide is really to address -- to give the ACRS members

12 a feeling on the magnitude of the effects of solar

13 gain, solar beating on thermal loading. And

14 calculations -- Westinghouse has actually -- we spoke

15 to it last week -- or three weeks ago that this load

16 is typically not considered explicitly. And it's a

17 very small effect. I think the ACRS said please show

18 me. And so we've come back to try to show you that.

19 First of all, the ACI code equations in

20 load combinations really build in margins. And so

21 with respect to the thermal cases, where we look at

22 thermal dead and live load, a factor of 20 percent is

23 increased to the thermal load to address maybe

24 uncertainties associated with small effects.

25 For the case of seismic and thermal when
186

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 it is combined, the seismic load is on the order of 80

2 percent of the overall load due to seismic. And the

3 thermal would be in the order of 20 percent.

4 And for that case, we looked at very

5 extreme delta Ts as in our standard plan. The range

6 of temperatures that we -- the ambient temperatures

7 that we design to range from minus 40 to 115 -- minus

8 40 in the winter and 115 in the summer. And that

9 design is the design that we applied to the plant at

10 Vogtle and the plant in Georgia and the plant in South

11 Carolina.

12 And we'd look at both the winter condition

13 and the summer condition. And you will see here --

14 this slide is showing that the winter -- the delta T

15 across the structure, across the wall, for the winter

16 condition is the most limiting. And it is 110 degrees

17 across the structure, 70 degrees on the inside of the

18 shield building and minus 40 degrees on the outside.

19 For the summer case, we look at the delta

20 T as 45 degrees out and 70 degrees inside and 115

21 outside. And so you see our limiting case is the

22 winter condition.

23 When we looked at the effects of solar

24 gain -- and we can go into how we came up that -- we

25 followed the ASHRAE standards that really provide the
187

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 equations of how to predict the temperature effects of

2 solar gain. For our shield building wall, those

3 calculations show a surface temperature of 129 degrees

4 for an ambient condition of 115.

5 So when you look at that, that would

6 really increase. And that's looking at -- I believe

7 115 day and night?

8 PARTICIPANT: That's correct.

9 MR. CORLETTI: So assuming day and night,

10 which is a pretty bounding effect -- the delta T for

11 that summer case would go from 45 to something like 59

12 degrees. Still bounded though by the winder condition

13 of 110 degrees.

14 So the effect of solar gain in the

15 wintertime would really, in effect, lower that delta

16 T -- lower the 110 degree delta T.

17 VICE CHAIRMAN ARMIJO: To get that 129, is

18 that for a painted surface with high reflectivity? Or

19 is it for --

20 MR. BAKER: A light colored surface.

21 VICE CHAIRMAN ARMIJO: Light colored

22 surface. Okay. So you plan to paint this coating

23 that's on it.

24 MR. BAKER: Right.

25 VICE CHAIRMAN ARMIJO: Okay.
188

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. CORLETTI: So really when we do these

2 calculations, we really show that for the AP1000

3 shield building, the design calculations that we've

4 already done really bound any effect of solar gain

5 that we could have envisioned.

6 We did also look at radiative cooling. So

7 we have thought about that. And we have looked at

8 that.

9 Tod, do you want to speak to that?

10 (No response.)

11 MR. CORLETTI: Okay. So with respect to

12 the radiative cooling, in the wintertime, the surface

13 temperature is on the order of -- on a minus 40 degree

14 day -- jump in if I'm wrong -- it's something like

15 minus 30 degrees.

16 So the effective emissivity due -- in that

17 cold condition would be a couple of degrees. So it

18 would be one or two degrees in the range of -- on the

19 factor of --

20 MR. TUNON-SANJUR: It would be a small

21 factor -- 22 for the cylindrical wall, the industry

22 standards say that emissivity, that radiative cooling

23 is negligible.

24 PARTICIPANT: For a vertical surface.

25 MR. TUNON-SANJUR: That's right.
189

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. CORLETTI: For the vertical surface,

2 I'm sorry, thank you, Tod.

3 So basically the ACI standards, it would

4 say you take no panel before for emissivity. So the

5 limiting delta Ts is still the 110 F that you did the

6 calculations for.

7 (Chorus of agreement.)

8 MR. CORLETTI: We did perform additional

9 calculations just to see what was the impact on the

10 stresses for the summer case, for the limiting summer

11 case with that 129. And it was -- it's on the order

12 of a couple percent increase in the stresses due to

13 the effect of solar gain on the summer case, which

14 again was the non-limiting case.

15 The next issue that -- and the final issue

16 in the structural area was on the issue of the PCS

17 tank. And I think this, to explain, what the issue

18 here was is that the analysis that was described in

19 DCD 18 did not reflect a commitment that Westinghouse

20 had made to the staff to address an issue as part of

21 the shield building report.

22 The shield building report has identified

23 how the design -- the hydrodynamic loads to the PSC

24 tanks should be accounted for in a certain way. And

25 that did not get reflected in the DCD. And we've
190

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 subsequently updated the analysis and provided those

2 results in DCD 19. I'll give you a little bit more

3 explanation.

4 Just to digress a bit, in the hard rock

5 certification that was included in DCD 15,

6 Westinghouse performed equivalent static analysis,

7 applying maximum acceleration for time history

8 analysis for the structure, including the PSC tank.

9 And that was what was certified.

10 Next slide please. When we went to the

11 extension to soft soil, we did change our analysis

12 method to use a response spectrum analysis using what

13 we call the NI05 global model. In that and in the

14 DCD, we identified that we would use the NI05 model to

15 design the structure, including the PCS tank.

16 However, in portions of the roof, that was

17 a more complicated structure that maybe was not

18 adequately represented in that global NI05 model, we

19 did retain an equivalent static methodology with a

20 more detailed model. And we applied those results

21 from that equivalent static method for the air inlet

22 ad tension ring region. And that was what we had

23 described in the DCD Rev 16 through 18.

24 Next slide. In the review of the shield

25 building, I think the staff really asked us to perform
191

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 the design of the PCS tank using that more detailed

2 equivalent static model not only for the air inlet and

3 tension ring but also to apply it to the PCS tank.

4 And we self identified after we submitted

5 Rev 18 that we had not included those results from

6 that equivalent static method that we applied for the

7 air inlet and tension ring to the PCS tank. So what

8 we did is we subsequently updated the analysis results

9 in DCD 19 to use -- to reflect the more detailed

10 method of the equivalent static method not only to the

11 air inlet and tension ring but also to the PCS tank.

12

13 So essentially DCD 19 is really the same

14 methodology as was done in the certified hard rock

15 site of DCD 15. And that is now all included and the

16 job site is now better. This is one of the areas

17 where that licensing basis has clearly then identified

18 in the DCD.

19 MEMBER SHACK: But that required no

20 changes in the actual design itself?

21 MR. CORLETTI: That resulted in no changes

22 to the reinforcement or to the structure or to the

23 design. We did do updated calculations using that

24 method. But as far as results or as far as the

25 physical structure, it did not change.
192

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 That ends the structural portion of the

2 presentation unless there's questions from the

3 members.

4 MEMBER RAY: If nothing else, we can come

5 back. Your guys aren't going to run to the airport

6 are they?

7 MR. ZIESING: Nope, we'll be here.

8 MEMBER RAY: We'd better move on to the

9 containment.

10 CHAIRMAN ABDEL-KHALIK: On Slide Number 6,

11 you made the argument that when you include solar

12 radiation, the outside surface temperature increases

13 to 129 degrees so the delta T in the summer increases

14 but is still sort of limited by the -- or smaller than

15 the 110 degrees.

16 Does the sign of the gradient matter at

17 all? Whether it's a positive gradient or a negative

18 gradient in the radial direction?

19 MR. TUNON-SANJUR: Yes, we designed the

20 structure as a symmetric structure both the

21 reinforcements, whether the stresses are on the

22 outside or the inside. The signs do matter in that

23 there will be -- in the summer condition there will be

24 more tension in the outer plates versus the cold

25 condition in the winter.
193

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Those are more of a localized stresses.

2 The delta T was emphasized by Mike Corletti because

3 the overall wall, the delta T dictates the bending of

4 that wall.

5 In the localized area, those things do

6 matter. However the study that we did for the thermal

7 cycling, we actually have a much higher gradient than

8 this 59 degrees of solar gain there. So answer to

9 your question, yes, it does matter. That localized

10 stress area had already been analyzed and accounted

11 for for a different reason than thermal cycling using

12 just --

13 MEMBER SHACK: But I think he was asking

14 even in the overall structural response, which is what

15 you're really doing in this particular case, you know,

16 does the fact that you've got the delta Ts going

17 different ways make a difference.

18 MR. BAKER: And we looked at both cases.

19 And the envelope considers both cases.

20 MEMBER SHACK: Yes, I mean the statement

21 was even though you -- with the 129, it was still

22 smaller. You actually did the calculations. And the

23 winter delta is still the limiting one. So they did

24 -- they actually did the calculations.

25 CHAIRMAN ABDEL-KHALIK: Okay, so it's not
194

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 just a simple argument that the delta T is small then

2 the case for the winter. And therefore, it should be

3 okay.

4 MEMBER SHACK: The smaller delta was where

5 we were, I think, at the Subcommittee meeting. This

6 now essentially so it verifies what you sort of

7 expected with the rather are difference in the delta

8 T, it's okay.

9 MEMBER BLEY: But just to follow that up

10 because I'm curious, the bending is going to reverse

11 directions when you change that. And the points were

12 that while it connects top and bottom, it must behave

13 very differently whether you're bending this way or

14 that way. So is there something of an additive effect

15 in summer or winter? And the opposite in -- one of

16 those must be worse. 

17 So you've done the calculations. So which

18 one of those is worse and kind of why just to inform

19 me.

20 MR. TUNON-SANJUR: The winter condition,

21 it's -- we designed both sides of the plate

22 symmetrically. And so we take the worst thermal, in

23 this case in the inner portion, the winter condition

24 would be worse, add it to SSC --

25 MEMBER BLEY: I didn't ask it right. If
195

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 you had the same delta T --

2 MR. TUNON-SANJUR: Yes.

3 MEMBER BLEY: -- summer and winter because

4 the bending is reversed, which of those cases would be

5 the most troublesome if one were in troublesome?

6 MR. TUNON-SANJUR: I would say summer

7 would be for the solar gain.

8 MR. CORLETTI: No, I think he said at 110

9 in winter versus 110 in summer, which is the worst

10 case. In our thermal cycling study, I believe the

11 reason we presented it in the thermal cycling case,

12 that 110 degree delta, because we showed it as a

13 winter case was the winter results were a little bit

14 worse. Do you agree with that?

15 MR. TUNON-SANJUR: The seismic changes

16 sides in both directions.

17 MEMBER BLEY: Okay.

18 MR. TUNON-SANJUR: So it really -- so for

19 us, whether the inner plate or the outer plate is

20 worse, it's interesting but we -- like I said, we take

21 the worst condition of either one of those two plates

22 and assign both plates the same.

23 MR. BAKER: But we have combinations that

24 consider both sides of seismic and both sides of

25 thermal.
196

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. CORLETTI: And we combine it. It's

2 because they're looked at when we combine it with

3 seismic.

4 MEMBER CORRADINI: Okay. Did you get your

5 answer?

6 MEMBER BLEY: Not quite. I think I know

7 what they're saying but I'm not sure.

8 So I think from what you just said that

9 the problem area is the plate itself. So it doesn't

10 matter whether it's bending one way or the other.

11 MR. TUNON-SANJUR: The winter conditions

12 say the inner plate.

13 MEMBER BLEY: It's not the connection

14 points.

15 MR. TUNON-SANJUR: Right. Both are

16 designed symmetrically. In winter condition, the

17 inner plate combined with SSC would be worse.

18 However, we designed the outer plate just the same.

19 MEMBER BLEY: For the same loading.

20 MR. TUNON-SANJUR: And then for the same.

21 And then in the summer condition, the outer plate

22 would be worse. It would be the same. The signs

23 would be reversed. And then we designed it. I would

24 say the winter condition in general would be worse

25 because you would have an additional effect of
197

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 buckling of those plates instead of shrinking.

2 MEMBER BLEY: That's what I was trying to

3 get to. Yes, okay. Thank you.

4 MEMBER SHACK: But it is a hypothetical

5 anyway because the delta Ts --

6 MEMBER BLEY: Yes, I got it.

7 (Laughter.)

8 MR. ZIESING: Are we ready to move to the

9 containment vessel pressure? Or are there more

10 questions for these guys?

11 MEMBER RAY: I'd like to get on with

12 containment evaluation.

13 MR. ZIESING: Okay. Thank you very much.

14 And don't feel slighted.

15 MEMBER BANERJEE: So some part of this is

16 open and some of it is closed? Or what?

17 MS. McKENNA: This is Eileen McKenna from

18 the staff. We're going to try to proceed with this

19 session as open as possible. It is possible that to

20 answer fully some of the questions, we may need to go

21 to a closed session. And we'll climb that if it

22 arises. And that's what we'll have to do because we

23 want to make sure your questions do get answered.

24 MEMBER RAY: Eileen, so that we don't go

25 back and forth, I guess we will have to save those
198

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 things to make sure we've got them all if we implement

2 a proprietary session.

3 MS. McKENNA: Right.

4 MEMBER RAY: Okay.

5 MR. ZIESING: Let's go guys. It's like a

6 hockey game. Fresh lightning here now.

7 PARTICIPANT: Just don't fly them in on a

8 Yak-42.

9 MR. ZIESING: Okay. So we're going to

10 lead discussion on the questions related to the

11 containment pressure analysis. We have Tom Kindred,

12 Rick Ofstun, Brad Carpenter up here. And I think Kent

13 Bonadea is over in the wings if we need him.

14 And I think, Rick, you're going to lead

15 discussion here?

16 MR. OFSTUN: Yes.

17 MR. ZIESING: Okay. I'll drive.

18 MR. OFSTUN: Okay. Good afternoon. I

19 guess you already introduced us all.

20 This is essentially the same presentation

21 that was made three weeks ago. However, we tried to

22 address some of the questions and concerns that came

23 up during that meeting.

24 First just a brief history of where we are

25 with the containment pressure analysis or how we got
199

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 to where we are. Back in DCD Revision 18, we had a

2 peak pressure of 57.8 psi gauge. ACRS member

3 questioned the scaling of our time to establish steady

4 state water coverage.

5 We found that that needed to be corrected.

6 And made that more conservative. And as a result,

7 that increased our calculated peak containment

8 pressure to 58.1 psi gauge.

9 That happened around the February-March

10 time frame this year. At that same time, we

11 discovered or we became aware of several generic

12 issues that are related to the containment analyses

13 and the calculation of the LOCA mass and energy

14 release inputs.

15 And so we were requested to make some

16 additional input changes to our LOCA mass and energy

17 release model and containment model inputs to address

18 those issues. And those changes --

19 MEMBER BANERJEE: How did those issues

20 come to light? Did the staff do an audit? Or --

21 MR. OFSTUN: No, internal -- Westinghouse

22 internally, we just discovered we had not selected as

23 conservative inputs as we could have. And so --

24 MEMBER BANERJEE: For the mass and energy

25 release?
200

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. OFSTUN: For the mass and energy

2 release calculations.

3 MEMBER BANERJEE: And what was missing

4 there? Just remind me. Was it some structures

5 inside?

6 MR. OFSTUN: Yes, there were some -- I

7 have a list here. Steam generator secondary pressure

8 -- we used the pressure in the steam line rather than

9 in the tube region of the steam generator. We hadn't

10 realized that we were doing that.

11 The steam generator pressure in the tube

12 region is about 30 psi higher. And as a result, the

13 initial stored energy in the steam generator is

14 higher.

15 MEMBER BANERJEE: I'm really interested to

16 understand what was the process that you went through

17 to find this. Did it just happen by accident? Or did

18 it happen --

19 MEMBER SHACK: Did you do an internal

20 audit? I think that's what --

21 MEMBER BANERJEE: Yes, was it an audit?

22 Or when this issue arose, did you --

23 MR. ZIESING: I think there's -- I'll try

24 to address this at first. There's no single reason

25 for the variety of input changes. As part of design
201

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 finalization, auditing, you know, just the different

2 looks that occur.

3 There's various reasons that identified

4 the minor discrepancies. And as part of our

5 corrective action program, they are captured in our

6 correction action program.

7 And any time any one of those is

8 identified, the impact is evaluated and actions are

9 identified. And up to that point in time, each of the

10 discreet issues had been evaluated to be minor and

11 were basically queued up to be put into a correction

12 at some later date, okay?

13 MEMBER BANERJEE: So they had accumulated

14 over a period of time?

15 MR. ZIESING: So some of them had

16 accumulated over time and they were in our corrective

17 action system. We knew about them. Maybe there was

18 not situational awareness, you know, of them until

19 this issue with the steady state film coverage came to

20 bear and we started looking at updating the

21 calculation.

22 And that caused people to -- as part of

23 updating those calculations, you look in your

24 corrective action program. And there's also just, you

25 know, knowledge that people have to say hey, there's
202

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 these other factors out there. What do we do?

2 And so internally, they sought guidance

3 from Licensing. And we had some consultation with the

4 staff. And it was decided that the right thing to do

5 is to go ahead and sweep all these things into this

6 update.

7 MEMBER BANERJEE: But just -- the staff is

8 not going to appear in front of us because they've

9 finished their final SE of course. And we're

10 reviewing this after the final SE.

11 So -- but just from -- to get some

12 clarity, did the staff come and do an audit or

13 something of this mass and energy release at about

14 this time? Or what happened?

15 MR. ZIESING: No, we self identified the

16 issue. These were generic issues so they effected all

17 Westinghouse plants. And we informed the staff. And

18 I can't -- do you remember? Was that February or

19 March time frame?

20 And of the -- there were a number -- there

21 five to six issues that were generic that were

22 discovered. And of those, two impacted the AP1000

23 design.

24 MEMBER BANERJEE: And you discovered them

25 yourself?
203

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. ZIESING: I didn't discover them but

2 other people within Westinghouse did, yes. And as a

3 result, obviously then we asked ourselves, you know,

4 is there anything else. What's the extent of

5 condition? And we did our own independent assessment

6 of extent of condition.

7 Customers formed a team as part of the

8 design center working group, came in and took a look

9 at, you know, our CAPS program, make sure we didn't

10 miss anything. And then there was also an AIA

11 inspection that the staff conducted that the scope of

12 that inspection was expanded to include a review of

13 our corrective action program.

14 And so, you know, it was looked at to some

15 degree in that context as well. So if you're asking

16 because, you know, is there anything else out there

17 and are we going to change it again -- I think we

18 shook the tree pretty hard --

19 MEMBER BANERJEE: Okay.

20 MR. ZIESING: -- to make sure that we

21 captured everything that we needed to at this point in

22 time.

23 MEMBER BANERJEE: That was part of the

24 question obviously.

25 CHAIRMAN ABDEL-KHALIK: But from a generic
204

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 standpoint, do you have any way of checking for latent

2 errors? Not just related to this particular

3 calculation.

4 MR. ZIESING: Could you elaborate on your

5 question a little bit?

6 CHAIRMAN ABDEL-KHALIK: Well, there may be

7 some other areas for some other calculations. Is

8 there a QA program where you periodically do --

9 MR. ZIESING: Yes.

10 CHAIRMAN ABDEL-KHALIK: -- sampling checks

11 to make sure you don't have any latent errors in your

12 documentation?

13 MR. ZIESING: The answer is yes. We do

14 have a program that looks at that. Our corrective

15 action program is a very comprehensive program where

16 we set a very low threshold for identification of

17 issues that first should be identified and put into

18 CAPS -- into our corrective action program.

19 Each item goes through a weekly screening

20 review of a cross section of the business experts so

21 we can levelize the issues. And periodically there's

22 trending done to understand, you know, are there a

23 series of small order issues that are looking like a

24 trend that we have to, you know, take a harder look at

25 to understand. So --
205

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER RAY: Rolf, I think the issue here,

2 you referred to it as situational awareness -- was

3 there some lesson learned from the fact that these

4 things were known but had not yet been incorporated

5 that based on that lesson learned, you feel that that

6 situation doesn't exist or won't exist in the future

7 in which there are recognized problems but they are

8 accumulating before you issue a revision?

9 I mean this is a common thing to have

10 happen, a backlog of corrective actions. But that I

11 think is what we're asking about here. Not so much

12 that there's an error that you haven't discovered but

13 there's not timely action taken in the event that --

14 MR. ZIESING: I feel confident that our

15 system is sound and protects us against that type of

16 thing.

17 Some of the nuances with this particular

18 issue, you know, we're -- there were some judgment

19 calls made in terms of, you know, what is the

20 significance of this. And it was, you know, we wanted

21 to be transparent and, in fact, I'll say initially

22 there wasn't alignment within the staff on the need to

23 deal with this, okay?

24 And we probably, you know, lost a couple

25 of months in terms of being able to jump on this and
206

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 put it to bed because initially we thought that these

2 small errors didn't need to be included at this time

3 because they were not considered to be significant.

4 But because -- then it was realized it is

5 related to a tech spec and there was some legal

6 involvement that, you know, it's really important as

7 we certify the rule, if we have any known knowledge of

8 a tech spec being in error, that we didn't want to

9 have any uncertainty associated with that.

10 And so, you know, we went ahead and made

11 the correction. But technically it was viewed as

12 insignificant. But it was a matter of principle, you

13 know, and setting the right standard for the tech

14 specs. It was something we decided we were going to

15 correct.

16 And we don't think we have -- I'm not

17 aware. We've looked, okay, broader. I'm not aware of

18 any similar situation. And if we did encounter

19 something like that, then we'd have to identify it and

20 do the right thing.

21 MEMBER BANERJEE: Sure. It has sort of

22 strong legal implications once you go into rulemaking,

23 right?

24 MR. OFSTUN: We didn't want an question

25 regarding the tech spec requirement for the pressure
207

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 test, you know, to come up and cause a wrinkle in the

2 rulemaking process.

3 MEMBER BANERJEE: Okay. Let's go on.

4 Sorry. At least you've clarified that.

5 MR. OFSTUN: Thank you.

6 So after making all those changes to the

7 model, our final result here is that our peak pressure

8 for DCD Rev 19, that's reported in DCD Rev 19, is 58.3

9 psi gauge.

10 The approved modeling methodology that is

11 applied in the LOCA mass energy release and

12 containment response evaluation models is

13 conservative. I think we had a question the last time

14 on whether we're using a best estimate method or a

15 conservative method. It is a conservative method.

16 We try to select conservative input values

17 to bias the initial stored mass and stored energy in

18 the system for the mass energy release. And we try to

19 bias the mass energy release so that we dump the

20 energy out as quickly as possible.

21 We also try to select conservative input

22 values to bias the containment pressure calculation in

23 an upward direction. And those conservative input

24 values would be things like that would reduce the

25 condensation rate on the inside or the heat transfer
208

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 rate to the outside.

2 MEMBER BANERJEE: But as far as I know,

3 you are using correlations which you multiply by some

4 number.

5 MR. OFSTUN: Yes.

6 MEMBER BANERJEE: But the number seems to

7 me to be just one standard deviation lower than your

8 best estimate.

9 MR. OFSTUN: Yes, that is what it is.

10 MEMBER BANERJEE: Yes, so it is not

11 particularly conservative.

12 MR. OFSTUN: It's more conservative than

13 nominal, yes.

14 MEMBER BANERJEE: Yes. But --

15 MEMBER CORRADINI: There's no methodology

16 for containment analysis the way there is for peak

17 clad temperature if that's where you're going.

18 MEMBER BANERJEE: Yes.

19 MR. OFSTUN: Right.

20 MEMBER BANERJEE: So it's not an

21 evaluation model in the usual sense of what we do for

22 peak clad temperature? Okay. So it is a little

23 conservative, not completely.

24 MR. OFSTUN: Okay.

25 MEMBER RAY: There's no claim that it is
209

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 bounding in other words.

2 MR. OFSTUN: No, it's not bounding.

3 MEMBER BANERJEE: It's not two or three

4 derivations.

5 MR. OFSTUN: No, it's only one standard

6 deviation on those multipliers, yes.

7 So in addition to the changes to the mass

8 energy release model inputs, we made changes to the

9 containment model inputs. And those changes were

10 either corrections to make the calculation more

11 conservative or they were to reflect updated plant

12 design information.

13 After making those changes, we found that

14 our containment peak pressure was too high. And in

15 order to maintain it within the design basis, we had

16 to take credit for existing heat sinks that are in the

17 plant and in the model but not turned on normally.

18 And I guess our other goal is to try to maintain about

19 the same amount of margin that's reported in the DCD

20 Rev 18 in this new model.

21 MEMBER BANERJEE: Could you just elaborate

22 a little bit on this? If I understand it, since you

23 are trying to shave this peak pressure, you need heat

24 sinks which have a fairly rapid response. So things

25 like the grating clearly do because they're there. So
210

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 they are short term, so responding -- quick-responding

2 heat sinks -- long-term responding heat sinks.

3 Did you use most of the short-term

4 responding heat sinks that you could?

5 MR. OFSTUN: No.

6 MEMBER BANERJEE: Okay. So what other

7 short-term responding heat sinks are there other than

8 these gratings?

9 MR. OFSTUN: We used grating that we knew

10 were --

11 MEMBER BANERJEE: Rapidly responding.

12 MR. OFSTUN: -- well, that we knew that we

13 had data for that we were confident was not going to

14 be changed.

15 MEMBER BANERJEE: Okay.

16 MR. OFSTUN: So we selected the gratings

17 that were in the CMT compartment, for example.

18 There's a big --

19 MEMBER BANERJEE: Right.

20 MR. OFSTUN: -- floor in there that's a

21 large heat sink for us. We hadn't included these heat

22 sinks previously because the design had not gotten to

23 the point where it was certified for construction.

24 And so we were instructed don't include

25 the floors, the gratings, that kind of thing because
211

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 they may change in the final design -- or the

2 properties may change.

3 MEMBER BANERJEE: So what else is there

4 potentially?

5 MR. OFSTUN: Well, so we used the grating

6 in the CMT compartment. We used some gratings in the

7 accumulator compartments. We used some gratings that

8 were above the operating deck as well. But I believe

9 there's more gratings that we aren't -- haven't

10 credited yet.

11 MEMBER BANERJEE: Are they deeper down?

12 MR. OFSTUN: No, there's -- and there's

13 some additional heat sink above the operating deck

14 that we haven't credited yet.

15 MEMBER BANERJEE: In a reasonably well

16 mixed region.

17 MR. OFSTUN: Yes, in the reasonably well

18 mixed region. That would be, for example, the HVAC

19 ductwork.

20 MR. KINDRED: The HVAC ductwork is a

21 galvanized metal. None of the cranes are credited,

22 only the girder on the polar crane itself. The hoist

23 on the polar crane is not credited. The gip crane is

24 not credited. The fuel-handling crane is not

25 credited.
212

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 In reality, these were easy --

2 geometrically, the gratings were easy to represent.

3 A as far as trying to geometrically represent the

4 effective heat transfer service area of a crane or a

5 crane hoist, that's a little more complex.

6 MEMBER BANERJEE: Of course it's hard to

7 do heat transfer calculations on gratings. But when

8 you did that, you sort of just took the vertical

9 surfaces in the grating, did a sort of slab type

10 calculation. Is that what you did?

11 MR. OFSTUN: We did a slab calculation.

12 We calculated --

13 MEMBER BANERJEE: Has this been done

14 before? Have other people done this? Or have you

15 done it for other Westinghouse plants?

16 MR. OFSTUN: In our standard analyses,

17 usually we have a lump parameter, single volume

18 containment model. And there are ten to 12 heat

19 sinks. So I'm not sure if some of the gratings are

20 included in one of those ten or 12. But most likely

21 they are but I can't say for certain.

22 MEMBER BANERJEE: So WGOTHIC, when you --

23 was authorized in some way to handle this? Mike is

24 nodding so he knows this stuff.

25 MR. OFSTUN: There's a -- the validation
213

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 report for WGOTHIC and for our AP600, AP1000

2 containment models is WCAP 15846. And in there it

3 discusses how we conservatively model the effects of

4 circulation and stratification. And those effects on

5 the condensation heat mass transfer inside the

6 containment.

7 MEMBER CORRADINI: So just one thing on

8 that. When WGOTHIC has been validated, this is the

9 lump parameter version, not the distributed parameter

10 version.

11 MR. OFSTUN: That's right. This is --

12 MEMBER CORRADINI: You've not gone through

13 the validation of the other version of GOTHIC where

14 you essentially saw more of a CFD formulation.

15 MR. OFSTUN: That's right. We -- I think

16 we started down that path and then we switched to the

17 lump parameter path when we were working --

18 MEMBER CORRADINI: I thought so. I just

19 wanted to make sure. Okay.

20 MEMBER BANERJEE: Yes and so the

21 methodology is accepted by the staff --

22 MR. OFSTUN: Yes.

23 MEMBER BANERJEE: -- and has had previous

24 applications to --

25 MR. OFSTUN: Yes.
214

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER BANERJEE: All right.

2 MR. OFSTUN: Yes. And the modeling

3 methodology for the containment was compared to test

4 data.

5 MEMBER BANERJEE: Okay.

6 MR. OFSTUN: At least for GOTHIC code, for

7 a number of different --

8 MEMBER BANERJEE: So the gratings now

9 become the --

10 MR. OFSTUN: Yes, and that's the next

11 bullet there. That those heat sinks have been added

12 as a Tier 2* item.

13 MEMBER BANERJEE: Can we -- are you going

14 to visit this question of the accumulator that arose

15 during the Subcommittee meeting and the effect of

16 whether isothermal or adiabatic and potential effects,

17 if any at all on the containment pressure?

18 MR. OFSTUN: Yes, Tom's looked into that.

19 MEMBER BANERJEE: Could you just make a

20 statement for the record on that?

21 MR. KINDRED: Could you -- could I ask

22 you, Dr. Banerjee, to elaborate your question just a

23 little bit? What exactly --

24 MEMBER BANERJEE: Well, the reason I'm

25 asking it is that there was an issue about whether the
215

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 discharge from the accumulator was presumed to be

2 under adiabatic conditions or isothermal conditions.

3 And there was some discussion about under what

4 conditions the density should be taken.

5 MR. KINDRED: Okay, yes, Dr. Banerjee, I

6 understand.

7 MEMBER BANERJEE: If you recall --

8 MR. KINDRED: I recall it.

9 MEMBER BANERJEE: Yes.

10 MR. KINDRED: Dr. Wallis, I think, brought

11 that up when he reviewed the report.

12 MEMBER BANERJEE: Right.

13 MR. KINDRED: He noticed that when we

14 calculated the expansion of the accumulator, when we

15 determined what the mass flow rate was, we looked at

16 the variance and volume. And we said okay, if we push

17 this much volume out, to convert it to a mass flow

18 rate, you have to know the density.

19 So you assume the density at 120 degrees

20 Fahrenheit as opposed to minus 140, which is what we

21 calculated the final gas temperature to be. So at

22 minus 140, of course the density of the gas is going

23 to be much larger than it would be at 120. So he

24 wondered if that was an error or a, you know,

25 something that we should have considered more
216

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 conservatively.

2 I redid the calculation and we stated --

3 we did both calculations in the analysis. We did an

4 isothermal and an adiabatic.

5 The isothermal yielded a much larger

6 volume expansion into containment than the adiabatic

7 heat up did -- 2,300 cubic feet as opposed to around

8 70 cubic feet -- 2,300 being the isothermal volume

9 expansion of the containment, 70 being the adiabatic

10 volumetric expansion and containment.

11 However, the 2,300 cubic feet volumetric

12 expansion was performed at 120 degree Fahrenheit. If

13 you did the volumetric expansion at minus 140, your

14 total volume expanded in the containment would be

15 about 376 cubic feet, which would yield a mass flow

16 rate of 6.15 pounds per second for both accumulators

17 as opposed to 20.8, which I believe was used in the

18 analysis.

19 So it was very conservative to assume the

20 isothermic. Even regarding the density. And it was

21 not erroneous because 120 degrees Fahrenheit was

22 consistent with the assumptions of the isothermic

23 calculation methodology.

24 MEMBER BANERJEE: And what is the effect

25 on containment pressure in terms of if you made it
217

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 additive or not? Is it a small amount like .01?

2 MR. KINDRED: The intensity of the psi.

3 And that's with the overly conservative calculation.

4 MEMBER BANERJEE: Two-tenths of the psi.

5 All right. Fine. May we put that to bed.

6 There was another related to the

7 accumulator but I don't know where we what to consider

8 that, which was the question of the temperature.

9 MEMBER SHACK: The effect of the

10 temperature on the pressure boundary?

11 MEMBER BANERJEE: Yes, well on the DVI

12 line in particular.

13 MR. OFSTUN: Yes.

14 MEMBER BANERJEE: So in particular, Bill

15 was going to discuss that? Or do you want to ask

16 those questions? Or do you want me to do it?

17 MEMBER SHACK: Well, we have the thermal

18 hydraulocists up now. We should have had the

19 structures people -- the question is whether you've

20 considered the thermal loading on that pipe and

21 whether it would have significant effect.

22 MR. KINDRED: I can answer this.

23 MEMBER SHACK: The load temperature, yes,

24 go ahead.

25 MR. KINDRED: Actually if you look at it
218

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 logically, your gas initial or thermal inertia, the

2 amount of energy that the gas can impart when compared

3 to water for instance, if you compared the mass of the

4 gas in the accumulator with the water, at a minus 140

5 degrees, the energy that the gas would have to -- if

6 the gas imparted all of its energy to heat the water

7 back up to 120 degrees, if the gas imparted all of its

8 energy to heat the gas back to 120 degrees Fahrenheit,

9 it could only change the mass of the water in the

10 accumulator by one degree -- less than one degree --

11 a half of a degree.

12 MEMBER BANERJEE: But that's all the water

13 right? But --

14 MR. KINDRED: That's correct.

15 MEMBER BANERJEE: -- if you put a thin

16 film of water on the surface, it would freeze.

17 MR. KINDRED: Right. You have

18 considerations regarding, you know, localized effects.

19 What happens at the gas liquid interface? What

20 happens at the discharge of the accumulator?

21 So a simple simulation using the GOTHIC,

22 this is different from WGOTHIC.

23 MEMBER BANERJEE: But GOTHIC is a lump

24 parameter, right?

25 MR. KINDRED: Actually, a simple model was
219

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 made with an accumulator tank, nodalized to contain a

2 blanket of nitrogen gas with liquid benefit at 120

3 degrees Fahrenheit. The LOCA accumulator injection

4 flow rates from the calculation for the limiting

5 temperature decrease associated with accumulator

6 expansion was used. And pulled the liquid and the gas

7 out of the accumulator.

8 The DVI line -- a five-foot section of DVI

9 pipe was modeled just at the discharge of the

10 accumulator line. And in reality, the temperature --

11 the surface temperature of the inside of the

12 accumulator tank was approximately 115 degrees after

13 -- at the end of injection or about a -- I let it run

14 for 150 seconds after the end of injection to allow

15 the gas to expand into the DVI line to ensure there

16 would be no pronounced thermal gratings associated

17 with the gas.

18 The DVI line itself, surface temperature

19 decreased to approximately 110 degrees. The DVI line

20 is very thin, approximately .312 inches. I don't know

21 if I can get into that detail in an open session

22 however the DVI line is thin. It easily promotes a

23 rapid response with regards to convective cooling.

24 MEMBER BANERJEE: Could we take the detail

25 up in a closed session because there are a number of
220

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 questions here we need to pursue. First of all, of

2 course the applicability of GOTHIC to a situation like

3 this where you can get cold gas on top of hot gas. So

4 you can get curious effects with GOTHIC that are hard

5 to defend.

6 Secondly, you know, these are transient

7 effects and the heat transfer proficiencies on the

8 inside of the line and the natural convection outside

9 --

10 MEMBER SHACK: I realize you have a great

11 interest in the thermal hydraulics of this. But from

12 a structural point of view, if we have some thermal

13 stresses on this pipe, it's, you know, one cycle of

14 perhaps some plastic stress. This is not going to

15 fatigue. You know, it's not a broken material. You

16 know, it's going to yield.

17 MEMBER BANERJEE: I'm happy to hand this

18 over to you.

19 MEMBER SHACK: If we did this once a year,

20 we might have a problem over 60 years.

21 MEMBER RAY: Let us -- we're just now

22 beyond halfway in our time. So let me do suggest that

23 Bill engage any discussion here or provide his

24 assessment. And then we'll see if we can move on.

25 MEMBER SHACK: Yes, I mean that's my -- my
221

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 argument is that, you know, whatever questions you

2 have about the thermal hydraulic analysis and the

3 temperatures, it would have no impact on the

4 structural. That, you know, we could take the whole

5 temperature drop, calculate it as conservatively as

6 you want.

7 MEMBER BANERJEE: Well, I think that's the

8 issue. If it's the bounding face of minus 140 or

9 whatever --

10 MEMBER SHACK: Right.

11 MEMBER BANERJEE: -- and if you can live

12 with, then it doesn't matter.

13 MEMBER SHACK: Now Graham, he had a

14 thermal shock picture in mind. And you just don't

15 thermally shock stainless steels. They take plastic

16 string at any temperature you want to give it to them.

17 And so from a structural point of view, I

18 don't think there's any problem here. And, you know,

19 we probably ought to pursue the thermal hydraulics as

20 an --

21 MEMBER BANERJEE: But we don't need to.

22 MEMBER SHACK: Yes, okay.

23 MEMBER CORRADINI: I can concur.

24 MEMBER BANERJEE: But I'm only doing it

25 because you don't seem to want to pursue it.
222

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER SHACK: I don't really trust it but

2 --

3 MEMBER BANERJEE: Yes, all right.

4 MEMBER CORRADINI: And I think what we did

5 commit that this piping, the structural design of the

6 piping is part of the piping DAC. It's not part of

7 the certification.

8 So you're absolutely right. The thermal

9 hydraulic trains that gets characterized for this

10 transient, this isn't a condition 2 event. It is a

11 condition 4 event, which we don't do fatigue

12 evaluations. So we would look at the stresses to meet

13 condition 4 events. And that documentation will be

14 included one way or another as part of the piping DAC,

15 the final piping DAC.

16 MEMBER RAY: Okay. But from our

17 standpoint, we would -- because we don't necessarily

18 agree with the temperatures you'd be using, it would

19 be better if we could simply bound it and say it is

20 not significant rather than to say we will do it and

21 keep track of it.

22 MEMBER BANERJEE: Or do something which if

23 you need to get the transient -- my suggestion would

24 be not to do it with GOTHIC. But that's up to you.

25 MR. KINDRED: I will say, Dr. Banerjee,
223

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 that I did benchmark the model to the isothermal

2 expansion case. And the model did very well

3 predicting what we predicted with the isothermal

4 expansion. And it is interesting that the nitrogen

5 injection, those were benchmarked to the Spazenosa

6 test. I mean so that was -- those were prototypic

7 nitrogen injections. And they did agree with what

8 they predicted in an isothermal expansion case.

9 MEMBER BANERJEE: Okay.

10 MR. KINDRED: But prior to adding -- and

11 all I did that after that, after I benchmarked to the

12 isothermal case was add the thermal conductors to

13 simulate heat sink or heating to the environment,

14 heating from the sensible heat of the accumulator

15 metal and --

16 MEMBER RAY: Again, insofar as what Dr.

17 Shack talked about, I think it is better at this point

18 if we bound it and conclude that from our standpoint

19 it is not -- we don't need to pursue it or make the

20 assumption that you have proven it to be true.

21 MEMBER BANERJEE: Or it will be dealt with

22 elsewhere.

23 MEMBER RAY: Well perhaps.

24 MEMBER BANERJEE: Yes.

25 MEMBER RAY: As long as there is not -- I
224

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 just don't want to get into trying to make sure we

2 agree with the last statement made here, because that

3 will take us forever and we won't achieve our aim.

4 MEMBER BANERJEE: Okay. Well I think it

5 is fine. Let's go on.

6 MR. OFSTUN: Okay, the next plot shows a

7 comparison of the DCD Rev 19 to the DCD Rev 18

8 containment pressure response. And the reason for

9 this plot originally was to show that they are very

10 similar and that the containment pressure increase

11 early in the event is what caused the peak to be

12 higher at about 1200 to 1500 seconds.

13 We were asked about this plot to find out

14 why the pressure response on the DCD Rev 19 falls

15 below DCD Rev 18. That was the question. And so we

16 looked into that by doing some sensitivity studies and

17 found out that the reason is that the new mass and

18 energy releases shift or shifted toward the earlier in

19 time with the conservatisms that we have added and

20 they move earlier in time. And as a result, that plus

21 the fact that we have included some additional thin

22 metal heat sinks that absorb that energy early in time

23 and don't give up very easily, that the curve shifted

24 and crossed over the other curve.

25 MEMBER CORRADINI: So let me say it
225

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 different to you so I get it right, since I wasn't

2 here. So you are saying in your energy budget, what

3 you release is the same but it comes out earlier and

4 some of it is sucked up in your heat sinks that you

5 have now included.

6 MR. OFSTUN: Yes, our energy --

7 MEMBER CORRADINI: And they don't give it

8 back up to later than --

9 MR. OFSTUN: Right.

10 MEMBER CORRADINI: -- to where the red

11 line is.

12 MR. OFSTUN: Right. But our energy budget

13 wasn't exactly the same because we had added some

14 energy for this new generator pressure correction.

15 MEMBER CORRADINI: Excuse me. Okay,

16 excuse me. I'm sorry. That's right.

17 MR. OFSTUN: So it is still a little bit

18 higher than what we started with. We just, we do push

19 it out earlier because we changed our equilibration

20 value.

21 MEMBER CORRADINI: Okay.

22 MR. OFSTUN: So at the last meeting, the

23 ACRS requested further review concerning the impact of

24 solar radiation heating on our larger scale passive

25 containment cooling test results and how that
226

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 information is applied to our containment evaluation

2 model.

3 The primary modes of heat removal from

4 passive containment are condensation on the inside

5 surface of the shell and evaporation from the outside

6 surface of the shell.

7 We looked at all the test data. Only two

8 tests, the large-scale test and the small scale test

9 were performed outside in the sun or in the

10 environment. We did not use any of the data from the

11 small scale test facility for anything. But for the

12 large-scale test, we did look at the data in terms of

13 the condensation, heat-mass correlations and the

14 convection heat transfer correlation.

15 Again, we used the multipliers that we are

16 talking about for the condensation and the conduction

17 correlation and we don't use the convection

18 correlation in our model at all, actually.

19 When we looked into this, we found that

20 the solar radiation did not have any impact on the

21 large-scale test data that was used for validation of

22 the condensation heat mass transfer correlation. And

23 this was because the large-scale test is fairly well

24 instrumented and so we knew temperatures and heat

25 fluxes around this vessel, around the perimeter of
227

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 this vessel and on top of the dome. And when we did

2 the heat balance, the heat in from the steam was

3 approximately equal to the heat that was going into

4 the containment or into the steel shell of the large5 scale test facility.

6 MEMBER BANERJEE: Actually, you had more

7 than that but carry on. 

8 MR. OFSTUN: Okay.

9 MEMBER BANERJEE: Finish off.

10 MR. KINDRED: Not for the condensation

11 test.

12 MR. OFSTUN: The convection tests they

13 did. We did see a difference there.

14 MEMBER BANERJEE: No, no. I'm saying even

15 for the condensation tests that you did with the water

16 film, you had three heat balances if you look at of

17 when you are reporting contained.

18 MR. OFSTUN: Right.

19 MEMBER CORRADINI: To your credit.

20 MEMBER BANERJEE: So but you have a heat

21 balance based on how much condensed and you have a

22 heat flux meter in the wall? Then you have a heat

23 balance on the air and water stream.

24 MR. OFSTUN: Yes. 

25 MEMBER BANERJEE: Right? And you compared
228

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 all three heat fluxes.

2 MR. OFSTUN: I didn't compare the heat

3 flux on the water stream and air on the outside of the

4 vessel.

5 MEMBER BANERJEE: You have a figure in the

6 report 331 if you check it.

7 MR. OFSTUN: Okay.

8 MEMBER BANERJEE: You will see that they

9 are also there.

10 MR. OFSTUN: And that is in the large11 scale test data report?

12 MEMBER CORRADINI: The big monster report.

13 MR. OFSTUN: Okay.

14 MEMBER BANERJEE: Yes, 331 compares that.

15 MR. OFSTUN: Okay. I haven't looked at

16 that for a long time.

17 MEMBER CORRADINI: We recommend you might.

18 One of the engineers.

19 MEMBER BANERJEE: Who were the people who

20 did this test? Were you involved with this?

21 MR. OFSTUN: No, I was not involved with

22 those tests.

23 MEMBER BANERJEE: They are very nice

24 experiments, by the way, but the internal velocity

25 measurements didn't work worth a damn. 
229

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER CORRADINI: Yes, the turbine meters

2 were crappy.

3 MEMBER BANERJEE: Exactly. But they do

4 show a lot of interesting things. Because I agree, by

5 the way, with that first statement. I looked at it

6 myself in some detail.

7 MR. OFSTUN: Okay.

8 MEMBER BANERJEE: So you have independent

9 corroboration but I wanted you guys to say that as

10 well.

11 CHAIRMAN ABDEL-KHALIK: Okay. Let's say,

12 granted you may have extracted the correct data out of

13 the large-scale test facility, in doing the actual

14 calculation for the actual steel containment and

15 shield building, the incident solar radiation part of

16 it makes its way to the inside surface of the shield

17 building. If you are looking at it on a steady state

18 basis. Right? And therefore, that heat flux has to

19 be removed by the natural convection air that is

20 ultimately used to remove decay heat through the film.

21 And therefore, there is an increased heat load on the

22 liquid film. 

23 Is that accounted for in your calculation?

24 MR. OFSTUN: No. We do not model the

25 solar heat flux on the outside of the shield building
230

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 and the effects of that through the shield, as it

2 conducts energy through the shield building and into

3 the air.

4 CHAIRMAN ABDEL-KHALIK: Would that have an

5 impact on the heat load? I mean, you know, the

6 incident solar radiation on the shield building can be

7 as high as a few megawatts. And part of it --

8 MEMBER RAY: Of course, we're no longer

9 talking about the large-scale test. We are talking

10 about the real world.

11 CHAIRMAN ABDEL-KHALIK: Correct.

12 MEMBER RAY: Up until you asked that

13 question, we had been talking about the large-scale

14 test.

15 CHAIRMAN ABDEL-KHALIK: Correct. And I

16 started my statement by saying granted, you may have

17 extracted the correct data out of the large-scale test

18 facility and now you are using that data to calculate

19 the containment pressure and the effectiveness of the

20 film in cooling, in removing decay heat essentially.

21 So we are saying that incident solar

22 radiation on the shield building, part of it, will

23 make its way to the inside surface of the shield

24 building and, therefore, will make its way to the

25 natural convection air that is used to remove decay
231

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 heat from the liquid film. And if that is the case,

2 this is effectively the same as increasing decay heat.

3 Has that been accounted for?

4 MR. OFSTUN: I have to think about that.

5 As I said earlier, we do not model solar heat flux in

6 the containment model. We don't add a heat term to

7 the outside of the shield building. It would be a

8 variable over time. So, it might be the other way and

9 during the day it is in.

10 CHAIRMAN ABDEL-KHALIK: Right. You know,

11 you can't assume when the accident is going to happen.

12 MR. OFSTUN: That's right.

13 CHAIRMAN ABDEL-KHALIK: But being a

14 pessimist, the accident will happen during a time of

15 the day when the heat flux is maximum, you have a lot

16 of heat being conducted across the shield building to

17 the inside surface.

18 MR. KINDRED: Dr. Khalik, there is a film

19 of water on the exterior containment --

20 CHAIRMAN ABDEL-KHALIK: I understand. I

21 understand. Look at it globally.

22 There is heat coming in that is being

23 removed by the downward flowing air current on the

24 inside surface of the shield building. And that air

25 is going to make it back up, removing the heat by
232

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 evaporation from the thin film.

2 So you have essentially hotter air that is

3 being used to cool the film.

4 MEMBER RAY: It would be like an increase

5 in the ambient air.

6 CHAIRMAN ABDEL-KHALIK: Correct. Has that

7 been taken care of?

8 MR. CORLETTI: Can I try to answer part of

9 the question before you do that?

10 We presented to you the surface to the

11 solar gain on an increase of 14 degrees on the outside

12 plate. That gradient does not work this way all the

13 way through the structure.

14 So the inside wall, inside structure --

15 What's the increase? 

16 CHAIRMAN ABDEL-KHALIK: Whether it works

17 its way all the way through the structure or not,

18 there is some finite heat flux on the inside surface

19 of the shield building.

20 MR. CORLETTI: So I think the answer is we

21 did not account for that increase on the inside

22 temperature. It is less than one or two degrees. It

23 is on the order of one or two degrees on the inside.

24 CHAIRMAN ABDEL-KHALIK: It is not a matter

25 of how high the temperature is. It is a matter of
233

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 what is the inside surface heat flux and what that

2 contributes to the heat load.

3 MEMBER RAY: As we said, it is equivalent

4 to increasing the ambient air temperature, in a sense.

5 MEMBER BANERJEE: Let them answer this.

6 MEMBER RAY: Okay. I'm just trying to

7 avoid the argument that it is only a degree or two

8 because the wall is so thick.

9 Actually the air flows from the outside to

10 the inside.

11 MEMBER BANERJEE: Right.

12 MEMBER RAY: And the issue is if you heat

13 the outside, what effect will that have not just on

14 the inside surface of the shield building but also on

15 the air that is flowing into the space.

16 MR. OFSTUN: That would be probably

17 higher.

18 MR. KINDRED: And I will say that --

19 MEMBER RAY: Of course it would be.

20 MR. KINDRED: -- in the evaluation of the

21 enhanced shield building design for Revision 18 of the

22 DCD, the air in that area was reduced by approximately

23 40 percent. I don't know the exact numbers there, but

24 it was reduced significantly, which would have caused

25 a significant decrease in the airflow you are talking
234

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 about.

2 That significant decrease in that airflow

3 did not result in an impact to the pressure valves.

4 CHAIRMAN ABDEL-KHALIK: But these are all

5 sort of qualitative arguments.

6 MR. KINDRED: Well you had mentioned the

7 air temperature. And the air temperature is important

8 but so is the airflow. So is the air velocity. In

9 that region you decrease the air velocity, decrease

10 the amount of mass airflow in that region and still

11 have no impact because the primary mode of cooling is

12 the evaporation of the film, due to conductive heat

13 from the shell not from what the air is doing to the

14 outside of the film.

15 CHAIRMAN ABDEL-KHALIK: Now at 1300

16 seconds, is 1300 seconds is the time at which you

17 reach roughly the peak containment pressure. At that

18 point, decay heat is how many megawatts?

19 MR. KINDRED: I don't know off the top of

20 my --

21 CHAIRMAN ABDEL-KHALIK: Roughly two

22 percent.

23 MR. KINDRED: Two percent?

24 CHAIRMAN ABDEL-KHALIK: Right. Two

25 percent that means what, 60 megawatts. 
235

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 So what would be the effect of increasing

2 decay heat by a few megawatts?

3 MR. OFSTUN: The decay heat's very small

4 impact at the time of peak pressure, most of that

5 energy that is due to the heat coming out of the steam

6 generators and not of the RCS metal. I don't have the

7 numbers in front of me but the decay heat will come

8 out continuously. But it is after about 10,000

9 seconds, all the energy is decay heat in our model and

10 none of it, because we dump everything else out into

11 the containment atmosphere from the RCS.

12 MEMBER BANERJEE: I guess he is asking how

13 much decaying heat are you putting out.

14 MR. KINDRED: He's asking what is the

15 contribution of decay heat at the time of peak

16 pressure.

17 MEMBER BANERJEE: No, not decay heat.

18 Solar radiation.

19 So let's say the solar radiation is a

20 couple of megawatts, two to three at most. I mean, my

21 calculation shows actually, depending on the angle --

22 MR. OFSTUN: On the real containment?

23 MEMBER BANERJEE: Yes, it is not that

24 high. But let's say it is a few megawatts, two or

25 three megawatts. But you are dumping what? How many
236

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 seconds or whatever? That is really the question he

2 is asking you.

3 MR. OFSTUN: How much we are evaporating

4 at the time of peak pressure?

5 MEMBER BANERJEE: No. How much heat are

6 you dumping inside of containment that you have to

7 take care of. Or what is the heat you are losing?

8 What percentage of this would be the solar insulation?

9 MR. OFSTUN: Oh, okay.

10 MEMBER BANERJEE: It would be one percent,

11 105 percent, 1005 percent? What is the number?

12 MR. OFSTUN: I would need to know the

13 total and I don't have that off the top of my head

14 either. Is Bob Jakub on the line?

15 MEMBER BANERJEE: Around the maximum peak.

16 I mean, really what we are after is can it affect the

17 peak pressure significantly at all. That is the

18 question. That is what they are after.

19 MEMBER RAY: To the extent that it is

20 equivalent to raising the ambient temperature, I don't

21 see how it could not. But I keep coming back to this

22 is a problem of basically equivalent to raising the

23 ambient temperature. I don't want to try and answer

24 for you beyond that.

25 MEMBER CORRADINI: I mean, you are asking
237

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 a quantitative question. Unless you have exact

2 quantitative things you are not going to get an answer

3 for it.

4 My quick estimate is the solar flux is no

5 more than about one or two megawatts out of 70.

6 CHAIRMAN ABDEL-KHALIK: But the problem is

7 the peak containment pressure is, the margin is so

8 small and that is why these questions keep coming up.

9 What is the effect of the incident solar radiation on

10 the peak containment pressure, even though it is

11 indirect heating?

12 MEMBER CORRADINI: But the heating is not

13 -- The heating is affecting the inlet air temperature.

14 It is not affecting what is appearing on the

15 evaporative surface of the containment shell. Right?

16 CHAIRMAN ABDEL-KHALIK: You can look at it

17 anyway.

18 MEMBER CORRADINI: But I mean, that is

19 what is effecting. So my question would be, have you

20 considered the effect of the inlet air temperature and

21 how it effects the pressurization inside? That is the

22 parametric I would do. Because if you vary the inlet

23 air temperature, how do you change the peak pressure

24 inside containment?

25 MR. OFSTUN: It is relatively insensitive
238

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 to that because evaporation is the key heat removal.

2 MEMBER CORRADINI: During that time

3 period.

4 MR. OFSTUN: Yes. We run cases,

5 sensitivities to air temperature and they are

6 documented in the WCAP 15846 and I think it is in

7 section ten.

8 MEMBER BANERJEE: Well that would be

9 helpful, I think, to refer to that.

10 MR. OFSTUN: But again, I don't have this

11 in front of me.

12 MEMBER CORRADINI: My way of interpreting

13 at least in my mind is that is the question to ask.

14 If I am uncertain about the inlet air temperature due

15 to essentially whatever is happening on the outside of

16 the building, how does that affect peak pressure? If

17 the answer is it doesn't affect the pressure more than

18 a tenth of a psi, then you need to know a

19 quantitative, you have got to be pointed to some

20 quantitative place to look at that.

21 MEMBER BANERJEE: I think that is a fair

22 way to look at it, what Mike is saying.

23 MEMBER RAY: Okay, in the interest of

24 time, and given that we have the staff and a member of

25 the public to hear from also, can we table this and
239

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 ask you to come back with it at a time the chairman

2 will fix hopefully yet today and resume the

3 discussion? Otherwise, we are just going to burn up

4 time here that we can't afford to do.

5 MEMBER BANERJEE: Have we dispositioned

6 the effect of solar radiation on the correlations that

7 are used? Because the question that was asked was

8 specifically since you used the large-scale test for

9 validation of your correlations, did solar radiation

10 affect the validity of the validation process of these

11 correlations?

12 MR. OFSTUN: And our answer is that it

13 didn't affect the condensation correlation.

14 MEMBER BANERJEE: And that is the only one

15 you used?

16 MR. OFSTUN: And that is the only one that

17 I used the large-scale test for.

18 MEMBER BANERJEE: Now moving on to the

19 convection case, what did you find? Even though you

20 did not use it, since you brought it up, now you have

21 to. How did you find it affected it?

22 MR. OFSTUN: Well what we found is that we

23 either thought that the impact of it of the solar

24 radiation on the dry convective heat transfer test

25 caused the outer temperature to be higher than what it
240

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 would have been otherwise. And what we saw when we

2 compared the heat rates from inside the vessel through

3 the steam and the heat flux times area in the shell,

4 that they did not balance. That that heat flux was

5 lower than it should have been.

6 MEMBER BANERJEE: Which was lower?

7 MR. OFSTUN: The delta T.

8 MEMBER BANERJEE: Which is what you would

9 expect. Right?

10 MR. OFSTUN: Yes.

11 MEMBER BANERJEE: So in which direction

12 did the solar radiation take it?

13 MEMBER RAY: Conservative or non14 conservative?

15 MR. KINDRED: Conservative because it

16 would have under-predicted the measured body of the

17 heat transfer of the convected heat transfer

18 coefficient.

19 MEMBER BANERJEE: Can we put that on the

20 record? We agree with you.

21 MEMBER CORRADINI: This is, as he said,

22 the convective tests? I'm sorry, the convector test?

23 MR. OFSTUN: Yes, the dry convective test.

24 MR. KINDRED: It is the impact of solar

25 radiation on the measured convection heat transfer
241

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 coefficient would have been to bias the measured heat

2 transfer coefficient in a conservative direction.

3 MEMBER BANERJEE: Right. There's a good

4 -- I mean, if you do the math, you can show that.

5 MR. KINDRED: Absolutely. I mean, the

6 result of the solar radiation impedance of solar

7 radiation or solar flux is going to be to heat the

8 shell. If the shell temperature, your Q equals HA

9 delta T, the delta T is smaller. Therefore, your

10 convective heat transfer coefficient will be smaller,

11 which is conservative.

12 MEMBER BROWN: It will do what? The

13 convective heat transfer coefficient will do what, H?

14 MR. KINDRED: No, the convective heat

15 transfer coefficient simply is Newton's law of cooling

16 Q equals HA delta T, where delta T is the surface

17 temperature of the containment vessel as opposed to T

18 infinity or the surface temperature of the air.

19 The effect of solar radiation would be to

20 heat the shell, the shell temperature, thus reducing

21 the delta T in the equation HA delta T. And you would

22 have, thus, you would measure a lower heat rate coming

23 out of containment, as opposed to a predicted which

24 would be conservative because you would have measured

25 a lower value.
242

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 So when you did your measure to predict it

2 and developed your mean and standard deviations, that

3 would have resolved itself as a greater standard

4 deviation because it would have created a greater

5 variance --

6 MEMBER BROWN: On the qualitative part,

7 not on the standard deviations.

8 MEMBER BANERJEE: Unfortunately the

9 argument he is making is qualitative but you can

10 actually do the sums. The equations --

11 VICE CHAIRMAN ARMIJO: The words on the

12 charts say the heat flux data were adjusted to account

13 for this impact. So that must have been done

14 quantitatively. Right?

15 MR. OFSTUN: Yes, we tried to do that.

16 VICE CHAIRMAN ARMIJO: So if you have done

17 it, you probably have some numbers.

18 MEMBER RAY: Let's bear in mind we are

19 talking about the -- not talking about the evaporative

20 cooling. Right?

21 VICE CHAIRMAN ARMIJO: No, I'm talking

22 about the second to the last sentence there. Solar

23 radiation and convection heat transfer correlation,

24 heat flux data were adjusted.

25 MR. OFSTUN: They were factored into our
243

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 data evaluation.

2 MEMBER BANERJEE: Yes, so what you did is

3 you corrected the data so that you could actually get

4 the right correlation. Otherwise, you would have

5 found the correlation was too conservative.

6 MR. OFSTUN: Yes.

7 MEMBER BANERJEE: Right. Let's put it

8 this way. You didn't use that data.

9 MR. OFSTUN: I didn't use that data.

10 MEMBER BANERJEE: You didn't use the

11 correlation. But if you did use the correlation, the

12 data would have been conservative.

13 MR. OFSTUN: Yes, probably. Now hindsight

14 is 20/20, I probably would not even have used that

15 data.

16 MEMBER BANERJEE: Right. Okay. By the

17 way, that data seems to be for a heavy water reactor,

18 from what I can see.

19 MR. OFSTUN: Yes, the large-scale test

20 facility was originally was the heavy water reactor

21 test facility. And that design did not use

22 evaporative cooling. It is air only cooling.

23 MEMBER BANERJEE: Okay. Can we -- There

24 were other anomalies which we won't go into right now,

25 the variation in heat flux, things like that.
244

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. OFSTUN: Uh-huh.

2 MEMBER BANERJEE: But I think that was due

3 to your plume rising and --

4 MR. OFSTUN: It could be internal or

5 external.

6 MEMBER BANERJEE: Fine.

7 MEMBER RAY: Conclusions. Something I

8 have been looking for.

9 MR. OFSTUN: All right. Model input

10 changes were made there were input changes to address

11 the items that affected the peak containment pressure

12 that is reported in the Tech Specs. We made no

13 changes to the plant design. Our calculated peak

14 pressure remains just under 59 psi gauge.

15 The NRC has reviewed the modeling changes

16 and requested additional information and found that

17 the changes and their responses to their questions

18 were acceptable.

19 With regard to solar radiation, we found

20 that there was no impact on the validation of the

21 condensation correlations on the large-scale tests and

22 that the impact from the convection correlation which

23 isn't really used, was addressed through the data

24 evaluation.

25 MEMBER RAY: Any further questions? We
245

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 will have Westinghouse come back with a discussion on

2 the effect -- to see what the data suggests the effect

3 would be of solar heating on the airflow that is drawn

4 in to the shield building annulus.

5 But at this point in time, I think, Mr.

6 Chairman, we should move on with the staff and have an

7 opportunity for our member of the public to speak to

8 us as well. Anything else you wanted to say?

9 MR. KINDRED: Yes. A ten degree increase

10 in the outside air temperature results in a 500th of

11 a psi increase to peak pressure. So of course, by 100

12 degrees would result in a half of a psi. So if you

13 heated the air by 100 degrees, you would increase the

14 peak pressure by approximately a half of a psi.

15 MEMBER RAY: If you could still -- You

16 have gotten that very promptly and we appreciate it.

17 If you could give us facts or by some means give us

18 something that we can all look at, rather than trying

19 to peer over your shoulder at your BlackBerry, I think

20 that would be appreciated, too, if you can do that.

21 Okay, with that, Eileen, come up here and

22 change places.

23 MS. McKENNA: Okay, as he said, I am

24 Eileen McKenna. I will have my staff colleagues

25 introduce themselves.
246

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. PATEL: Yes, my name is Pravin Patel,

2 NRO. I am a structural engineer in the structural

3 engineering garage.

4 MR. DROZD: And my name is Andrzej Drozd.

5 I will address containment issue, containment peak

6 pressure issue.

7 MS. McKENNA: In the interest of what

8 appears to be the committee's interest, I thought we

9 might start with the containment issues, rather than

10 the structural issues because that seemed to be that

11 that was generating greater attention.

12 So as soon as we get the slides up.

13 MR. BUCKBERG: My name is Perry Buckberg.

14 I am doing the slides.

15 MS. McKENNA: Sorry. That's my mistake.

16 I thought it said NRC. Here we are.

17 MR. BUCKBERG: I'll introduce the staff.

18 The staff has introduced themselves. I am a little

19 off base here but we have two presentations. We have

20 containment pressure that you just heard from

21 Westinghouse. We are going to give the staff's

22 opinion, the staff's views and analysis on that, a

23 very brief presentation and entertain your questions

24 as well. And we will follow that with a brief

25 structural presentation.
247

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER RAY: Thank you. Please proceed.

2 MR. DROZD: Okay, again my name is Andrzej

3 Drozd. And we did all the WGOTHIC calculation as well

4 as assumptions. And we went through the revision of

5 mass and energy release as well as the additional heat

6 sink added to the modeling.

7 And we don't have any issues with using

8 either revised mass and energy release as well as

9 added heat structures but we did want do our

10 independent confirmatory calculations. We used MELCOR

11 as was developed by Sandia for research two years ago

12 to analyze revision, I don't remember, 16 or 17. And

13 we modeled accordingly.

14 We added the heat structures to the model

15 as well we revised the mass and energy release. We

16 performed a number of parametric studies on the model,

17 as I will show a couple of slides down the road.

18 Let me give you the result, the summary of

19 our results. The heat pressure that we had, let's

20 call it originally with the old mass and energy

21 release and old heat sinks, give us surprisingly high

22 safety margins of almost four pound gauge. Using a

23 revised mass and energy release, decreased that safety

24 margin to 1.6 as we can see. And then this margin

25 increases as we added the heat sinks, additional heat
248

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 sinks. And the margin, according to our calculations,

2 will be or is 2.2 pound gauge. That is consistently

3 higher margin or the pressure is consistently lower

4 than the one calculated by GOTHIC and we can discuss

5 why is it.

6 MEMBER BANERJEE: Well before you go on,

7 Andrzej, maybe this is the time to discuss why is

8 this.

9 MR. DROZD: What is that? Oh, it is and

10 you will see a couple of slides below GOTHIC is using

11 a very conservative heat transfer coefficient of the

12 type of Tagami and Uchida, while MELCOR well for one

13 reason or another, the research in Sandia decided not

14 to implement directly Uchida and Tagami.

15 MEMBER CORRADINI: Because it's wrong.

16 MR. DROZD: That is one of the arguments.

17 MEMBER CORRADINI: That is not an

18 argument. It is wrong.

19 MEMBER BANERJEE: But I thought they were

20 validating these.

21 MR. DROZD: The way MELCOR is being used

22 for design basis analysis is based on studies of

23 containment pressure transients comparing to

24 contained, which uses Uchida and Tagami.

25 MEMBER CORRADINI: It is a heat mass
249

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 momentum analogy.

2 MR. DROZD: Analogy. But then contained

3 was qualified kind of based on comparing to contained,

4 very ancient code which does mass and energy balance,

5 rather than calculations.

6 MEMBER BANERJEE: But WGOTHIC was

7 validated against the large-scale experiments.

8 MR. DROZD: Yes and --

9 MEMBER BANERJEE: I mean, it must be

10 right. Right?

11 MR. DROZD: We never said they are right

12 but they are accepted.

13 MEMBER CORRADINI: Just one clarification

14 for Sanjoy because I want to make sure I understand.

15 So the 58.3 is with the modification where they

16 essentially did an automatic reduction in the

17 multiplier, is my understanding.

18 MR. DROZD: That is for Westinghouse

19 calculation.

20 MEMBER CORRADINI: The Westinghouse

21 calculation.

22 MEMBER BANERJEE: One standard deviation.

23 MEMBER CORRADINI: One standard deviation.

24 But it does have that effect in there. That's what I

25 was trying to understand.
250

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER BANERJEE: Yes but what they did is

2 for the one standard deviation for the inside is a

3 fairly substantial reduction by .28 so it is around

4 wherever. But outside is less. What did you do on

5 the outside with MELCOR?

6 MR. DROZD: Outside is a default

7 convective heat transfer calculated by MELCOR. I

8 don't know the name of this particular correlation.

9 It is a correlation.

10 MEMBER BANERJEE: But this is with

11 evaporating water in the chimney?

12 MR. DROZD: Yes.

13 MEMBER BANERJEE: But it was not tuned

14 against any data?

15 MR. DROZD: No.

16 MEMBER BANERJEE: All right.

17 MEMBER REMPE: Could you talk a little bit

18 about the additional heat conductors? Did you just go

19 with the assumptions provided by Westinghouse? Did

20 you audit them?

21 MR. DROZD: We audited the choice of heat

22 structures and there was a list of eight or nine heat

23 conductors that were added. And what I was given was

24 surface area and volume.

25 So what I did is I surface weighted
251

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 thickness based on those volumes which turned out to

2 be roughly a quarter of an inch and that sounded

3 reasonable to me, to us after discussion, because

4 grating would be just about two millimeters. So we

5 used that as a representative added structure.

6 So the added structures are 6.77

7 millimeters thick covered with epoxy paint and located

8 in a couple of different places that I will show you.

9 MEMBER BANERJEE: Let me ask you a

10 question which sort of has been in the back of my

11 mind. When you really look at these large-scale data,

12 there is a very wide variation around, depending on

13 wherever they are sitting and all sorts of things.

14 And has there been any analysis done of the scaling of

15 this? Because even those the large-scale facility is

16 fairly large, the real system is much larger.

17 MR. DROZD: Much larger.

18 MEMBER BANERJEE: Okay. So in fact, I am

19 wondering if that sort of averaging which is done

20 actually has any validity on such a large-scale. Is

21 there some evaluation being made of this?

22 MR. DROZD: The simple answer and short

23 answer is yes. We had a contractor, if I recall, from

24 Idaho. Many years ago they went through the scaling

25 analysis. He had some issues but eventually the
252

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 scaling numbers were accepted by us.

2 The averaging of heat flux evaluation of

3 heat transfer coefficient were always subject to

4 uncertainty. But what I believe convinced us was that

5 we can accept the model was the test that Westinghouse

6 performed with half of the shell being dry.

7 MEMBER BANERJEE: Right.

8 MR. DROZD: So the asymmetry with the heat

9 transfer turned out to be not such a big effect.

10 Somehow internally the condensation appears to take

11 place, regardless whether it is this half or the other

12 half wetted.

13 So we thought although uncertainty

14 definitely exists, we thought that since we have on

15 one side the amount of condensate on an inner surface

16 and another vibration on the outer surface, these two

17 roughly gives you the idea how much heat can be

18 rejected.

19 MEMBER BANERJEE: So for example, even in

20 this containment, the heat fluxes vary by almost a

21 factor of two.

22 MR. DROZD: Yes.

23 MEMBER BANERJEE: Right and maybe even

24 more. So yes, it is sort of reassuring that even when

25 you have cooling on one side, it takes care of it in
253

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 some way. But without a good physical understanding

2 of why that happens, it seems that the scale is much,

3 much smaller to sort of put your half on this

4 happening on a grand scale needs a little bit more

5 than that.

6 MR. DROZD: That is correct. However,

7 other applications of codes in general like MELCOR for

8 other cases show that the heat models that uses local

9 value of heat transfer coefficients are decent enough

10 and predict at least trends if not pretty good

11 qualitative values of pressures and temperatures that

12 we accept those definitely imperfect lump parameter

13 models and mass and energy analogy, mass and heat

14 analogy to a heat transfer based correlation to be

15 used in design basis.

16 MEMBER BANERJEE: That's fine when there

17 are big margins and this is not your ultimate heat

18 sink and all sorts of stuff. I mean, you can do that.

19 Here, we are sort of appealing to this as

20 taking care of our -- You know it is a much more

21 critical component here.

22 MR. DROZD: It is. It is. And what gave

23 us --

24 MEMBER BANERJEE: It is not pressure that

25 matters. It is how much heat have you lost that
254

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 matters.

2 MR. DROZD: That is correct. And there is

3 sufficient uncertainty about the peak pressure that

4 raised a lot of concern with first with 8600 and

5 81000. And as we decided that adding a non-safety

6 spray system is sufficient to cover the as we call

7 residual uncertainty with the issues that you raised.

8 And that is on the top of many layers of conservative

9 assumptions to begin with.

10 MEMBER BANERJEE: Well I would agree.

11 Because of the non-safety spray that you have but

12 Harold will maybe argue that you cannot think of it

13 quite that way. Right?

14 MEMBER RAY: Not with the staff having

15 only having one minute to go.

16 (Laughter.)

17 MEMBER BANERJEE: He would like to stay on

18 schedule. Okay. That's okay, Andrzej.

19 MR. DROZD: Okay. We have very briefly in

20 those remaining 35 seconds, I have three slides to

21 cover. 

22 This is the model that we used, nothing --

23 very few notes. And the location of the added heat

24 structures are marked with those stars. We pick out

25 the low end of then ends modeled to minimize the
255

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 effect, the potential effect. And the location is

2 volume four, which is south stimulator produced a

3 little lower peak pressure than the heat sinks in the

4 volume three, which is core makeup tank.

5 And here is the effect of a revised mass

6 and energy release. The red one and the blue one are

7 equivalent. The red one and the greenish is a kind of

8 an added fringe benefit parametric study. I didn't

9 notice when I received the input that this data was

10 used for various parametric studies. And at first I

11 was running it as if it was a best estimate heat

12 transfer coefficient rather than default value. So

13 here you see how MELCOR given all equal the

14 conservative heat transfer ranges of the peak

15 pressure.

16 The revised mass and energy release moved

17 as in the case of GOTHIC up from the peak pressure and

18 raised another couple of pounds.

19 And the final one is, the next one please,

20 is given the revised mass and energy release, the

21 location of those heat sinks whether it is in the

22 control volume or calculation of volume four or three,

23 gives slightly different results, according to

24 engineering judgment.

25 We did many more parametric study changing
256

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 heat transfer area or heat transfer coefficient by ten

2 percent plus minus ten percent. The results just

3 follow engineering intuition when you increase heat

4 transfer and heat sinks, you decrease peak pressure.

5 It is just as simple as that. These given all the

6 uncertainty, at least trends are calculated.

7 So that is what we did and I don't think

8 there is much more to be done about the peak pressure.

9 MEMBER RAY: Thank you. Eileen, you have

10 got more to say?

11 MS. McKENNA: Only that if there are any

12 questions about the structural aspects, we have our

13 structural reviewer here. But I will defer to you

14 whether there is questions and you want presentation

15 or you want move on.

16 MEMBER RAY: All right. Bill, anything

17 you want to direct to the staff?

18 MEMBER SHACK: No. We know they found it

19 acceptable. And I figure you are just going to tell

20 us that again.

21 MEMBER RAY: Yes, I mean you and I have

22 talked about the fact that what appeared Tier 2*

23 appears to me at least to be a judgment of what is

24 needed. And people can differ on that judgment. You

25 have made a judgment. And I guess I should ask any
257

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 reason that you would conclude now that there is

2 anything more that ought to be made Tier 2* in the

3 same manner?

4 MS. McKENNA: I will speak and then I'll

5 let the OCD people. I think we did make a judgment of

6 what we thought were the most important values,

7 parameters, dimensions, materials, that we would want

8 to have that applied to, particularly where as we said

9 and as you quoted, where we didn't have the code to

10 give us the fall back, if you will, on how you would

11 judge any differences. We were aware of some of the

12 issues that the consultant raised but I don't think

13 that the staff had a different opinion after seeing

14 that information. But I will see if there is --

15 MR. PATEL: Yes. Something I think what

16 I will insert is that I won't be adding some more to

17 that. And I think like said here, it is a matter of

18 analysis to have some of the matter of analysis that

19 question those data. Also we consider this data Tier

20 2*.

21 Then also we made it some of the critical

22 sections, some items like rates and other stuff that

23 we are attempting to include in Proprietary Report

24 602.

25 We did do an audit and looked at all the
258

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 tables they provided some of the parameters like the

2 coil and provided reinforcement issues that we want to

3 control that we have the design margin maintained up

4 to the construction and installations.

5 And also we will check the ITAAC to make

6 sure that the ITAACs are also see items are supporting

7 ITAAC and Tier 2* also supporting ITAAC. 

8 So that is what we did at while we did the

9 audit a couple of times.

10 MEMBER RAY: Okay, well as Bill mentioned

11 in his remarks, you have performance criteria. Well

12 perhaps somebody would like to see it, a design

13 specified under performance criteria.

14 The thing that I think I was glad to see

15 was that you recognize that Tier 2*, at least for the

16 items that you thought were necessary provide

17 something that merely being included in the current

18 design doesn't provide. And that is the whole point.

19 Okay. Mr. Chairman, we are about five

20 minutes late in terms of I perceive you may want to

21 provide the opportunity for a public comment at this

22 time?

23 CHAIRMAN ABDEL-KHALIK: Yes, please.

24 MEMBER RAY: So may I have -- Shall I turn

25 it back over to you for that purpose?
259

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 CHAIRMAN ABDEL-KHALIK: No.

2 MEMBER RAY: All right. We have been

3 advised and I think everybody has received at their

4 place a written statement with some slides by a member

5 of the public who I will now ask, hoping that the line

6 has been opened so she can respond to us, if Dr.

7 Sterrett is on the line and prepared to provide us the

8 oral comments.

9 DR. STERRETT: Oh, can you hear me?

10 MEMBER RAY: We can, indeed. Thank you.

11 Go ahead.

12 DR. STERRETT: Okay. I just joined about

13 a minute ago so I don't know what you have been

14 talking about.

15 MEMBER RAY: Almost everything. But it

16 doesn't matter because we are now attentive to what

17 you would like to say to us.

18 DR. STERRETT: Oh, okay. So some of the

19 things I have to say may be things that I really do

20 not need to emphasize. I don't know. 

21 So let's see, I didn't give you slides for

22 what I was going to present today. The slides that I

23 would have given were from the presentation to the

24 committee.

25 MEMBER RAY: Yes. Yes, and by the way, I
260

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 believe you had estimated you would need not more than

2 ten minutes. Is that correct?

3 DR. STERRETT: I didn't say but I think

4 that should be sufficient for today.

5 MEMBER RAY: All right. Well we are

6 running a little late. So if you would please

7 proceed.

8 DR. STERRETT: Okay. All right. So I am

9 saying this, I didn't know how much you talked about

10 it so I will just give the written text that I have

11 prepared.

12 All right. This is Susan G. Sterrett. I

13 am at Carnegie-Mellon University. And there is some

14 noise on the line. I wonder --

15 MEMBER RAY: I don't believe we can do

16 anything about it. We have experienced it before and

17 it would be best if you just proceed.

18 MEMBER SHACK: You are clear. You are

19 quite audible.

20 MEMBER RAY: You are clear. There is

21 noise on the line. I agree.

22 DR. STERRETT: Okay. All right. So just

23 to introduce myself prior to my academic structural

24 mechanics including systems design. I did some work

25 on Westinghouse passive plant design but I never
261

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 worked specifically on the AP1000. So the information

2 I have is just the information available to the public

3 through the NRC's website.

4 To summarize the presentation last time,

5 there were two issues. The first one was radiation on

6 the concrete chilled buildings that wasn't accounted

7 for in the analysis. And I said that because looking

8 at the temperatures that were considered, they only

9 considered the temperatures to be the same as ambient

10 air; whereas I pointed out that the range will be

11 wider. It will be colder in the ambient air or can be

12 and can be significantly higher than the ambient air

13 when the sun is shining.

14 The second issue was the large-scale test

15 and actually the small scale test, too, that were used

16 in WGOTHIC were outdoors in the sun. And the thing is

17 that the main effect these were not scale model tests

18 in the normal sense. They were meant just to

19 understand certain effects. And one of those was the

20 coefficient representing evaporative losses. The sun

21 aids in evaporation and the test result was the main

22 way that this was being carried out was through

23 evaporative losses.

24 So I would like to just say a few things

25 about each of these and they may be moot by now but I
262

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 guess it doesn't hurt to have the reasons down.

2 The first one was the response that was

3 given previously, hopefully not today, was that normal

4 thermal loads don't need to include this extra 30 or

5 40 degrees, that somehow you would only worry about

6 that if there was some sort of extreme heat wave that

7 only occurs once in a great while. These are everyday

8 things. Surface temperatures in the sun and the

9 ambient air temperatures and ones at night can be

10 lower than the air temperature.

11 The other thing was that some people just

12 felt that the effect would be negligible. And I had

13 pointed out to the subcommittee there were a vast

14 number of cases, not just a handful, but many in the

15 news about this year there is concrete roadways,

16 bridges, ramps, and other structures, have buckled.

17 Now in those cases, the risk to public safety isn't

18 large because they closed down the highway. They

19 demolished the old buckled portion and they replaced

20 it. But of course, a shield building is different.

21 You can't use the same standard of acceptability. It

22 is a water tank. It forms a passageway to the airway

23 needed for heat removal.

24 So that is why I felt that it couldn't be

25 ignored that the attitude well what we are doing in
263

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 the AP1000 with the SC models conforming to normal

2 practice for concrete use in these other industries,

3 that to me is not an acceptable response because it is

4 different, even if it is true. I didn't check it was

5 true.

6 So the technical cases that I cited in my

7 long letter, I think the eight-page one, shows that

8 that attitude of complacency that if we need you know

9 the sort of the way that concrete is normally designed

10 with respect to the temperatures we consider, is

11 already not the norm at the other federal agencies and

12 institutions. So I found papers that came out Oak

13 Ridge and out of the National Institute of Standards

14 in Technology to illustrate this. Okay and I said I

15 wanted to say that if you have trouble getting those,

16 I can send you a copy.

17 The second thing regarding issue two about

18 the large-scale test, there were several remarks that

19 seemed either puzzled by the concerns or missed it

20 because of the intuition that surely if the sun is

21 shining on the physical model, wouldn't that be

22 unhelpful in providing cooling. And I do understand

23 that argument but it is first of all kind of

24 complicated. But second of all, Westinghouse was

25 always saying that their analysis using WGOTHIC which
264

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 was validated by this test was that worst case was

2 cold and if they counted in extra heat from the sun,

3 it would help. So it is hard to see how you could

4 accept what Westinghouse says the results of WGOTHIC

5 is and yet have the intuition that sunlight is going

6 to make evaporation worse. So I wanted to say that it

7 shouldn't be dismissed on that basis.

8 I personally think that no generalizations

9 about whether a certain increase or decrease in any

10 single factor is going to reduce containment or not,

11 I don't see how that can be made. And the reason is

12 that -- So I don't make a statement either way because

13 containment cooling involves humidity and other

14 factors that affect conduction through the shell.

15 Radiation is only one of the mechanisms.

16 So the thing is that if all you were doing

17 was measuring temperature and if what you were doing

18 is measuring temperature in the large-scale test, I

19 mean, it is going to matter what the humidity is and

20 what the sunlight is. If you have intense sunlight

21 and low humidity, that is going to be very different

22 from the case of no sunlight and high humidity, even

23 if they are exactly the same temperature. That is why

24 I don't see how you can really draw too much if all

25 you have and I don't have access to the detail that
265

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 you ACRS members do, but it looked like they were just

2 measuring temperatures. I don't see how you can make

3 any conclusions and correlate cases on the basis of

4 temperature. And I think if you understand the review

5 on the basis of heat transfer, you have to agree with

6 that.

7 And so the problem I am wondering, and

8 again I don't have access to the data, but just what

9 people wrote in discussing how they applied it to

10 WGOTHIC, but if what they have is just temperatures,

11 then I would worry that the test is measuring the

12 things that you need to make the inferences to cases

13 that are not exactly like the actual large-scale test.

14 So what I said or meant to say is that if

15 they are going to use the large-scale test to

16 determine the coefficients of evaporative

17 effectiveness then whether or not it is in the

18 sunlight does need to be taken into account because

19 into sunlight would aid evaporation. I hope by now no

20 one considers that an objectionable statement.

21 Secondly, I point out the purpose of the

22 large-scale test is limited to certain aspects of mass

23 and heat transfer effects. And here I am going to

24 quote from the FSER. I think it was stated at some

25 point that Chapter 21, which is about the test and
266

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 validation of the computer codes has not changed since

2 the 2004 FSER and here is quote from that. 

3 "The experimental large-scale test is

4 designed to induce similar containment dome heat

5 transfer processes and circulation stratification

6 patterns. However, it is not meant to simulate

7 specific AP600 accident scenarios. The large-scale

8 test data is used to validate WGOTHIC computer code,

9 which will be used to analyze the containment."

10 And I note that the main conclusion of the

11 test is and I quote, "evaporation was the primary mode

12 of heat removal from the outside of the vessel;

13 approximately 75 percent of the total."

14 So it looks to me like the situation is

15 this, that because the test, the large-scale test is

16 not, and I guess the large-scale test did not separate

17 out heat of solar radiation which was present in the

18 large-scale test but will not be present in the AP1000

19 leaded steel containment from the effects of ambient

20 air temperature and humidity of air, we just don't

21 know. And I don't know how you are going to figure

22 out how to do that from the data if the data didn't

23 include humidity and solar radiation.

24 Now you might say well let's run some

25 WGOTHIC. Well you can't use WGOTHIC to answer that
267

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 because that would be circular.

2 And the test data, I am just wondering if

3 you have enough there if you didn't measure solar

4 radiation. Now you might ask how do you measure solar

5 radiation. And the way meteorologists do it is by

6 using evaporation. They should have done that when

7 they ran the LST if they were doing it outside. But

8 I don't see any indication that they did. So I am

9 wondering if the data isn't there, I don't know what

10 you are going to do.

11 The test concluded that most dominant

12 factor is cooling via evaporation but assumed it was

13 the same whether the equipment was in the sun or in

14 the dark. So it looks to me as though WGOTHIC uses

15 coefficients for evaporative loss based on the test

16 performed in the sun for which the data is not

17 available on how much of the evaporation was due to

18 the sun. So that is just conveying the problem.

19 So I have a lot more I could add but I am

20 assuming that the time is limited. So let me just add

21 one more thing. That why this has to get done before

22 design cert is granted is because that is it. I don't

23 think there are checks and balances until real nature

24 comes along, the real challenge in nature would come

25 along. And that is a concern, that there would be no
268

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 check and balance on it, no check on it or checks of

2 it until the real challenges comes in nature.

3 And why would I worry about this? Because

4 as far as I know, the ITAACs are not going to check

5 this error. And here is my worry, that they don't

6 test for actual heat removal capabilities in the

7 containment by this PCS, per se. The ITAAC criterion

8 is whether or not certain system parameters like flow

9 rates and so on, the flow rate of water being

10 delivered over the steel containment dome and such

11 things.

12 Now if you think about it, the claim of

13 adequacy of heat removal from the containment, that is

14 going to be based on this error. And it is really,

15 really important in the AP1000 and 600 because unlike

16 in any other operating plant, this is the ultimate

17 heat sink. It means every other system performing

18 post-accident heat removal, all it is doing is

19 collecting the heat and then passing it on to the

20 containment so that the passive containment can remove

21 the heat.

22 So the validity of conclusions about the

23 effectiveness of those systems in removing decay heat

24 is going to be based on these calculations performed

25 using WGOTHIC, too. And the WGOTHIC analysis
269

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 calculations about evaporative heat losses are exactly

2 what are in question by this error about forgetting

3 about the sun.

4 And I am going to stop there due to time.

5 MEMBER RAY: Thank you. Yes, you've used

6 the time and I think I would just say this to you.

7 Can you hear me all right, Dr. Sterrett? Evidently we

8 have been muted, although Dr. Sterrett hasn't been.

9 So she is not able to hear us in response. 

10 MEMBER BROWN: We were told the mute was

11 on a little while ago.

12 MEMBER RAY: Yes, I know. Is there any

13 way to un-mute it before she hangs up? Can you hear

14 me Dr. Sterrett?

15 DR. STERRETT: I'm sorry. I can't hear

16 anything. Is the connection good on your end? Can

17 you hear me?

18 MEMBER RAY: Evidently we --

19 MEMBER BROWN: We are all nodding our

20 heads.

21 MEMBER RAY: Our control room operator

22 went for coffee or something.

23 DR. STERRETT: I can't hear anything.

24 MEMBER RAY: Dr. Sterrett, can you hear

25 us? We will try one more time here.
270

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Okay, well having heard nothing then,

2 Weidong, please get a hold of Dr. Sterrett. Tell her

3 that we heard all of what she had to say and that we

4 would ask her to -- and we appreciate her input very

5 much -- to consult the transcript of the meeting today

6 as well as the letter that we will ultimately write.

7 And we believe we have received her input and included

8 it in our deliberations accordingly.

9 So try and give her a call as quickly as

10 you can. We did hear the mute set, as Charlie

11 mentioned. And since it didn't mute her, we had to

12 assume it was muting ourselves.

13 MR. HACKETT: Harold, it was apparently on

14 her end. We have confirmed.

15 MEMBER RAY: That is very odd. We were

16 able to hear her so she should be informed of that.

17 Okay. Well with that now that we had a

18 last thing which was, let me just check with

19 Westinghouse and see. Are you going to provide us

20 those data that we were asking for, which would give

21 us some visual sense of the effect of ambient

22 temperature on containment peak pressure?

23 MR. CORLETTI: Yes, they are preparing a

24 slide next door.

25 MEMBER RAY: All right.
271

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. CORLETTI: Did you want to do that --

2 MEMBER RAY: So we will do that later,

3 then if it is not ready now. Anything else you want,

4 Eileen?

5 MS. McKENNA: No, that's fine.

6 MEMBER RAY: Okay, back to you, Chairman.

7 CHAIRMAN ABDEL-KHALIK: All right. Thank

8 you very much. At this time we are scheduled to take

9 a 15-minute break. So we will reconvene at 20 minutes

10 to 4:00.

11 (Whereupon, the foregoing proceeding went

12 off the record at 3:24 p.m. and went back

13 on the record at 3:38 p.m.)

14 CHAIRMAN ABDEL-KHALIK: We're back in

15 session. At this time we will move to Item No. 5 on

16 the agenda, Draft Final Revision 2 to Regulatory Guide

17 1.115, "Protection Against Turbine Missiles." And

18 John Stetkar will lead us through that discussion.

19 MEMBER-AT-LARGE STETKAR: Thank you, Mr.

20 Chairman. And in the interest of time I'll make my

21 remarks short.

22 This is for the Committee's information.

23 Another of the reg. guides that have not been updated

24 in quite a while, I think the last update to this one

25 was in 1977. We heard from the Staff regarding a
272

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 prior version of this update back on October 4, 2010.

2 So luckily we made it under one year before we brought

3 it to the Committee.

4 The Staff has made some changes to the

5 reg. guide in response to some of our discussions

6 during the Subcommittee meeting. And I think with

7 that I'll turn it over to the Staff.

8 MR. LABINSKY: If I could, this is John

9 Labinsky. I'm the Deputy Director of Component

10 Integrity in NRR. And I would just like to do a brief

11 introduction as well.

12 As stated, we are here to talk about the

13 reg. guide on protection against turbine missiles. We

14 appreciate the opportunity to address the full

15 Committee today.

16 I'd like to start by saying this has been

17 a collaborative effort over multiple offices and

18 multiple divisions. Both NRR and NRO have been

19 working on this update to the reg. guide.

20 As mentioned, we did have a Subcommittee

21 meeting last October. We did revise the reg. guide in

22 response to comments provided and questions during the

23 Subcommittee meeting. Based on those changes, we also

24 decided to reissue the reg. guide for public comment

25 again. We had done that before the last meeting. So
273

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 we did address changes in response to those public

2 comments as well. Today we'll provide an overview of

3 the proposed final reg. guide and how we addressed

4 both the ACRS Subcommittee comments as well as any

5 comments we received from the public.

6 So with that what I'd like to do is turn

7 to our presenters today, Simon Sheng from Division of

8 Component Integrity NRR, Steve Jones from the Division

9 Safety Systems NRR and John Honcharik from our

10 Division of Engineering in NRO.

11 Gentlemen.

12 MR. SHENG: Okay. Good afternoon. I am

13 Simon Sheng of Division of Component Integrity NRR.

14 And this is a presentation on the proposed RG 1.115

15 entitled "Protection Against Turbine Missiles "

16 summarizing the effort of Division of Component

17 Integrity, Division of Safety Systems of NRR and

18 Division of Engineering of NRO with comments from

19 Division of Safety Systems and Risk Assessment of NRO.

20 The second slide.

21 For completeness, we are going to go over

22 the main subjects that we went through --

23 MEMBER-AT-LARGE STETKAR: We're a low

24 budget operation. I have to run your own slides.

25 (Laughter.)
274

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. SHENG: Yes. That we went through in

2 the Subcommittee such as the GDC 4 requirements, the

3 current NRC position on protection against the turbine

4 missiles, the enhancements in the proposed RG 1.115

5 and the rest. However, this time we are going to

6 focus on the resolution of the Subcommittee's comments

7 and the industry comments on the RG which incorporates

8 the Subcommittee's comments. Next one.

9 And now let me summarize ACRS Subcommittee

10 comments. The first is to clearly define the

11 structure, system and components to be protected and

12 then consider non-nuclear power plant experience,

13 consider risk-informed approach, provide turbine

14 missile risk goal for new reactors. And the fifth is

15 clarify use of Table 1 in RG and the use of barriers

16 in the RG. And the sixth, clarify when Table 1 in the

17 RG is applicable. And the last one is expand RG to

18 include detailed technical guidelines.

19 And except Item 5 and Item 6 which we have

20 provided much better explanations in our RG, we don't

21 think that it requires further discussion here. And

22 each of the remaining items will be addressed this

23 afternoon. Next one.

24 (Off the record comments.)

25 RG 1.115 is based on GDC 4 which requires
275

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 structure, systems and components important to safety

2 be appropriately protected against the effects of

3 missiles.

4 And the current NRC -- Number five, okay.

5 The current NRC position on protection against turbine

6 missiles offers three options. The first one is by

7 turbine orientation. And the second one is by control

8 of turbine missile generation frequency. And the

9 third is by missile barriers.

10 And the positions of using orientation and

11 barriers were stated in RG 1.115 since 1977. However,

12 the position of controlling turbine missile generation

13 frequency was only stated in the Hope Creek SER of

14 1986. In year 2007 when the NRC revised the entire

15 SRP and we took the opportunity at that time to revise

16 the SRP section on turbine missiles to include this

17 position on missile generation frequency. Next one.

18 The objections of the proposed RG 1.115 is

19 to assure that the turbine failure is a negligible

20 contributor to risk. It makes the RG self-contained

21 including all acceptable protection methods against

22 turbine missiles and clarifies the structure, system

23 and components to be protected from turbine missiles.

24 And ACRS comments wanted us to do even a

25 better job in this area. Basically, the SSCs to be
276

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 protected from turbine missiles includes safety

2 shutdown functions, for example, like makeup water,

3 heat sink and long-term decay heat removal. And also

4 these SSCs excludes functions necessary only for other

5 unlikely design basis events, for example, high-head

6 safety inject ion and containment. And our objectives

7 of the proposed RG 1.115 also include assesses

8 operating experience since 1977.

9 MEMBER-AT-LARGE STETKAR: Simon, before

10 you go to the next slide, I think we had some

11 discussion at the Subcommittee meeting regarding as

12 you mentioned a couple of bullets on this slide. And

13 one I recognize you've clarified the scope of SSCs

14 that need to be evaluated backing off from safety

15 related to important to safety so that we capture the

16 notion of non-safety equipment but important to risk

17 elements for new reactors.

18 The first bullet is something we did

19 indeed have some additional discussion. It says

20 "Assure turbine failure is a negligible contributor to

21 risk." Now the analyses require that we have

22 confidence that damage to SSCs important to risk

occurs at a frequency of less than 10-7 23 per year.

24 MR. SHENG: Right.

25 MEMBER-AT-LARGE STETKAR: How does that
277

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 specific numerical value for damage to SSCs important

2 to risk give us assurance that that damage is a

3 negligible contributor to overall risk when risk

4 assessments for new reactors are publishing total core

5 damage frequencies on the order of two or three times

10-8 6 for a factor of three to five lower than that

7 screening criterion? So how do we have assurance

8 that's negligible and negligible doesn't mean 10

9 percent. It means a very small fraction.

10 MR. SHENG: Right. I see. We are going

11 to address that in a later slide.

12 MEMBER-AT-LARGE STETKAR: Are you? Okay.

13 Thanks.

14 MR. SHENG: Okay. Thank you. So next

15 one.

16 This RG also reviews operating experience

17 since 1977 which is a year that we published the first

18 RG 1.115. And before the existence of NUREG-1275, it

19 is safe as our effort in that area because that NUREG

20 basically summarizes the operating experience before

21 1995.

22 However, for after 1995, we reviewed the

23 Licensee Event Reports (LERs) and International

24 Incident Reporting System and INPO Significant Event

25 Notifications and basically we wanted to see whether
278

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 there are important precursors or any reports which we

2 think is significant. So that we need to revise the

3 current P1 and P4 criteria. And I'm going to define

4 the P1 and P4 in the next slide.

5 MEMBER-AT-LARGE STETKAR: Before you do

6 that, do you have any sense of the number of turbine

7 operating years that are included in the dataset that

8 you have on this slide here? Is it a 1,000 turbine

9 operating years? Is it 10,000 turbine operating

10 years? Is it 100,000? Is it a million?

11 MR. SHENG: Do you mean for the one that

12 we went through, the LERs, and what's available in the

13 system we did not have tabulated the number of reactor

14 years?

15 MEMBER-AT-LARGE STETKAR: Okay. Well, in

16 the U.S., if we have 100 units we accumulate given

17 each unit has a couple of low pressure turbines or

18 maybe three 200 to 300 turbine years per year.

19 MR. SHENG: Right.

20 MEMBER-AT-LARGE STETKAR: That ball park.

21 MR. SHENG: Okay.

22 MEMBER-AT-LARGE STETKAR: So since 1995 15

23 years would give us a couple of thousand.

24 MR. JONES: NUREG-1275 included an

25 assessment, you know, a rough estimate of about 1,000
279

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 operating years before that time.

2 MEMBER-AT-LARGE STETKAR: But that was

3 obviously conventional, primarily conventional, units.

4 Right?

5 MR. JONES: No, that was nuclear.

6 MEMBER-AT-LARGE STETKAR: Those were only

7 nuclear?

8 MR. JONES: Right.

9 MEMBER-AT-LARGE STETKAR: Okay.

10 MR. JONES: 1995 there were -- Some plants

11 had operated for 20 years.

12 MEMBER-AT-LARGE STETKAR: Yes.

13 MR. JONES: Other plants only just a few

14 years.

15 MR. SHENG: And I'm going to -- After the

16 definitions of P1 and P4 we're going to present the

17 results, the summary of our evaluation of, our

18 surveying of, the operating experience.

19 First, let me define P1, P3 and P4. When

20 turbine missiles are controlled by limiting the

21 turbine missile generation frequency the ultimate

22 concern is the probability of failure of an essential

23 system caused by turbine missiles. And we call it P4.

24 And basically P4 is equal to P1 times P2 times P3.

25 And P1 is the probability of turbine
280

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 missile generation which is the emphasis of the

2 current NRC practice. And P 2 is the probability of

3 ejected missiles striking an essential system. And P3

4 is the probability of the struck essential system

5 losing its safety function. Next slide.

6 After this digression, let's refocus on

7 the review of turbine operating experience and

8 summarize our findings. And we found that an event in

1997 which give the point estimate of 1E-3 9 per turbine

10 year for destructive turbine overspeed event. We also

11 found that the turbine operating record has improved

12 in general during the past 15 years.

13 However, from this, we also found that we

14 have an unignorable number of events resulting in

15 scrams, shutdowns and outage delays per year. But no

16 major damage has occurred except a throwing of blades.

17 And based on this summary, we conclude --

18 CHAIRMAN ABDEL-KHALIK: What does

19 unignorable mean in this context?

20 MR. SHENG: Unignorable means that we have

21 several events a year which will cause scrams,

22 shutdowns and outage delays per year.

23 MEMBER CORRADINI: Are those overspeed

24 events or?

25 MR. SHENG: No, that is debatable. You
281

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 can say that these are precursors to overspeed. But

2 you can also argue they are not.

3 MEMBER CORRADINI: Can you give me an

4 example what you mean by a precursor to overspeed?

5 MR. SHENG: Precursor means that if --

6 MEMBER CORRADINI: I know what precursor

7 means. But can you give me a specific example so I

8 understand your point?

9 MR. SHENG: Okay. What I mean by

10 precursor is that if all the mechanisms fail designed

11 to function -- it failed. Supposedly failed, its

12 function and the other situation go on without stop.

13 Then eventually you would develop into an overspeed

14 scenario.

15 MEMBER CORRADINI: So some kind of control

16 function failed. But if you were to do a what it

17 would have carried you to an overspeed event.

18 MR. SHENG: Right. But it means

19 everything put in place works.

20 MEMBER CORRADINI: Okay.

21 MR. SHENG: That's why it didn't go from

22 step one to step four.

23 MEMBER-AT-LARGE STETKAR: Simon, we had

24 some discussion in the Subcommittee about these

25 numbers and those sort of qualitative assertion that
282

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 everything is improving and that we have documented

2 experience to demonstrate that improvement. It's not

3 clear to me that if we have some evidence in 1991 that

the frequency might 1E-3 4 or ten times higher than your

1E-4 5 limit. That primarily nuclear U.S. operating

6 experience for the last 15 years gives us a lot of

7 information to have confidence that that's somehow an

8 absurd anomaly.

9 And there's a quote I keep hanging up on

10 in the reg. guide itself. And I won't read the whole

11 paragraph. I'll just excerpt this last sentence.

12 "Many destructive overspeed failures that occurred in

13 recent years were caused by the failure of turbine

14 steam valves to close and to stop the flow of steam

15 even though a trip signal was generated."

16 And I don't care about the forensics. I

17 care about the phrase "many destructive overspeed

18 failures that occurred in recent years." That tells

19 me that there is some operating experience of many

20 destructive overspeed failures.

21 And I'm curious where the basis either for

22 that statement which causes me some concern about this

10-3 or 10-4 23 per year frequency. If you have evidence

24 to support the phrase "many destructive overspeed

25 tests that have occurred in recent years" I'm not sure
283

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 how confident I am in these frequency estimates.

2 So I'm really at a quandary in terms

3 resolving that phrase with this notion that "Well, we

4 really haven't collected a lot of data, but we know

things are getting better and 10 -4 5 is an okay

6 frequency for us to target because that's sort of

7 consistent with actual operating experience."

8 MR. SHENG: Okay. Thank you for quoting

9 that sentence to me. Okay. Because in this round of

10 effect we paid attention to your comments and we did

11 not read RG very carefully about the language that you

12 quoted. I believe that that quote probably was from

13 the NUREG-12 -- 

14 MEMBER-AT-LARGE STETKAR: It doesn't make

15 any difference where it's from.

16 MR. SHENG: I understand. I said it may

17 be a direct copy from that NUREG 1275. 

18 MEMBER-AT-LARGE STETKAR: It indeed is

19 from the text of the reg. guide.

20 MR. SHENG: So basically that means it's

21 prior to 1995. Yes. Because in recent years it

22 implied in the last five or ten years.

23 MEMBER-AT-LARGE STETKAR: That's what got

24 my attention.

25 MR. SHENG: Right. That wouldn't be
284

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 appropriate. So I reexamine that the wording to make

2 appropriate changes.

3 MEMBER-AT-LARGE STETKAR: Thanks. And it

4 is something by the way that we discussed during the

5 Subcommittee meeting because I'm if nothing else

6 pretty good about keeping notes. And my notes from

7 10/4/2010 note that I quoted the same quote at that

8 Subcommittee meeting. So maybe you didn't read the

9 transcript.

10 MR. SHENG: Yes. Sorry. When we put that

11 summary together we missed your then notion.

12 MEMBER-AT-LARGE STETKAR: Okay. Thanks.

13 MR. SHENG: As I said, we're going to

14 revisit that.

15 MEMBER-AT-LARGE STETKAR: The other -- Dr.

16 Abdel-Khalik's term is unignorable is not a very

17 quantitative term.

18 MR. SHENG: Yes. I believe there's a

19 better word.

20 Okay. So let me keep going on our

21 presentation. Continue our presentation. Let me make

22 a note.

23 MEMBER-AT-LARGE STETKAR: It's in the

24 section that talks about destructive overspeed

25 analysis.
285

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. SHENG: Okay. And so based on our

2 survey we conclude that we consider that the nuclear

3 power plant experience only. But that's also the

4 ACRS's comment to include the non-nuclear units.

5 However, when we revisit this issue we found out that

6 the nuclear operating practices, maintenance, testing

7 and inspections changed after the Salem 2 event.

8 That's a result that we don't believe that these

9 changes made by nuclear utilities and nuclear power

10 plant insurers and turbine manufacturers have been

11 completely implemented by non-nuclear power plants who

12 are not involved in the effort.

13 MEMBER-AT-LARGE STETKAR: What's the basis

14 for that belief? Because I suspect that if I'm a

15 large conventional power plant and I have 1,000

16 megawatt electric turbine out there I suspect my

17 insurance companies and my investors are pretty

18 interested in keeping that large expense income19 generating piece of equipment intact. And I might do

20 everything in my power to try to make sure that it

21 stays intact.

22 So it's not clear to me why there isn't

23 the same attention placed on testing and maintenance

24 of conventional plant turbines, large conventional

25 plant turbines, as there is to the nuclear industry
286

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 simply because we may have codified some requirements

2 for testing.

3 MR. SHENG: Yes. As I said, our argument

4 is that because the non-nuclear power plants were not

5 involved in the joint effort by the utilities, NRC,

6 insurers and the turbine manufacturer at that time.

7 So they may implement -- I would say that they may

8 have implemented something, some recommendation, by

9 the turbine manufacturers.

10 However, those guidelines provided by the

11 nuclear power plants insurers are strictly for nuclear

12 power plants. Whether they also implement some

13 recommendations to the non-nuclear power units are

14 really hard to find.

15 MEMBER-AT-LARGE STETKAR: I guess the

16 general question is you're discounting any operating

17 experience from large conventional plants or any

18 quantitative assessment of international nuclear

19 operating experience based on the assertion that

20 "Well, we have special rules in the United States. So

21 therefore only our turbines under our rules are valid

22 in our dataset."

23 MEMBER CORRADINI: I would expect that you

24 have potentially a database of ten times more

25 experience.
287

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER-AT-LARGE STETKAR: That's the whole

2 point or more. Much more.

3 MEMBER CORRADINI: Conservatively.

4 MEMBER-AT-LARGE STETKAR: If I just take

5 700 megawatt electric and above.

6 MEMBER BLEY: And from some of the people

7 we've talked with and asked about their experience

8 with the monoblock rotors, that sort of thing, they

9 refer to very broad experience in the conventional

10 power plants. That's where they started because of

11 the expense. There's got to be a big --

12 MEMBER-AT-LARGE STETKAR: International.

13 MEMBER BLEY: Yes.

14 MEMBER-AT-LARGE STETKAR: Yes. That's

15 right.

16 MR. HONCHARIK: Well, I guess. But there

17 are those manufacturers that like you said are going

18 to monoblock for the nuclear components. Basically

19 they do have separate turbines for nuclear

20 applications. They actually have separate

21 classifications for nuclear turbines.

22 CHAIRMAN ABDEL-KHALIK: That's because we

23 run on lousy steam. They have to design around it.

24 MEMBER-AT-LARGE STETKAR: But if you go

25 back to the observation that I'll leave out the quote
288

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 "many" that turbine destructive overspeed failures are

2 due primarily to failures of steam stop valves to go

3 closed and things like that. It may not be all that

4 sensitive to monoblock rotors. I mean that's

5 obviously an effect of the materials and things like

6 that. But the reliability of the turbine protection

7 trip steam shutoff systems which are primarily the

contributors to the calculated 1E-4 8 frequencies if you

9 look at the analyses it may not be that sensitive to

10 material property requirements for nuclear qualified

11 steam turbines versus any other large steam turbine

12 that the people are producing.

13 MR. HONCHARIK: Well, I think like Simon

14 said that phrase about the many of the destructive

15 overspeed I think that was from the original meaning

16 previous to 1997. There were some destructive

17 overspeeds caused by that.

18 MEMBER-AT-LARGE STETKAR: I'm aware of a

19 destructive overspeed that happened in South Africa.

20 When was it, Sam? Earlier this year or was it last

21 year?

22 VICE CHAIRMAN ARMIJO: Within the last

23 couple years.

24 MEMBER-AT-LARGE STETKAR: Within the last

25 couple of years. Indeed the steam stop valves didn't
289

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 go closed.

2 VICE CHAIRMAN ARMIJO: Yes.

3 MEMBER-AT-LARGE STETKAR: I don't know

4 whether it was a monoblock rotor. But it probably

5 didn't matter.

6 MEMBER SIEBER: Well, governor valves do

7 close. They're independent, but they're slower by

8 about a second which makes a big difference peak. At

9 coal fire plants --

10 VICE CHAIRMAN ARMIJO: Is the issue here,

11 John, that the population is needlessly restricted?

12 MEMBER-AT-LARGE STETKAR: The issue here

13 is that there's a general acceptance that the

14 frequency of destructive failures of turbines on the

order of 10 -4 15 is acceptable and consistent with

16 operating experience. And the assertion is that we

17 have operating -- Despite the Salem event that was

18 cited that we have operating experience that shows

that that 10-4 19 frequency is reasonable to use. It's

20 sort of a fundamental precept of this entire notion of

21 why we emphasize the frequency of turbine missile

22 generation that P1 number in Simon's equation there as

23 opposed to the integrated P1 times P2 times P3.

24 Essentially all of the regulatory guidance

25 is based on P1.
290

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. SHENG: Up to now, right.

2 MEMBER-AT-LARGE STETKAR: Up to now. This

3 allows some more flexibility which is an important

4 extension of this revision.

5 So the reason is if there's evidence to

6 support that notion that not only analyses but actual

7 operating experience say that there's no reason to

disbelieve something on the order of 10 -4 8 is

9 reasonable, that's fine. If there's evidence for some

reason to show that 10-3 10 might be more reasonable that

11 sort of throws into question a little bit of the

12 difference and the emphasis in terms of the guidance

13 and the level of detail of analysis that might be

required to justify that nominal 10 -7 14 degree of

15 assurance.

16 So that's the whole reason of trying to

17 look at additional operating experience to give us

18 confidence. Because looking at ten years of operating

19 experience of just the U.S. nuclear industry only gets

20 us a couple thousand turbine years, if that.

21 MR. JONES: But we do have evidence from

22 the U.S. operating plant experience that they are

23 better at testing the solenoid valves in particular

24 that initiate the trip cycle. Also there are

25 operating procedure requirements to periodically test
291

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 the steam emission valves and cycle them that I don't

2 think happen as frequently or nearly as frequently at

3 fossil units.

4 MEMBER-AT-LARGE STETKAR: Yes, the one at

5 South Africa came apart because they were doing the

6 test. So you have to be a little bit careful about

7 making assertions.

8 MR. JONES: During which tests? The

9 overspeed protection system test?

10 MEMBER-AT-LARGE STETKAR: Apparently they

11 were. I don't have all the details.

12 MR. JONES: Salem 2 is the same situation.

13 MEMBER-AT-LARGE STETKAR: Yes, that's

14 right.

15 MR. JONES: Bypassing one trip to test the

16 other in that circumstance.

17 MEMBER-AT-LARGE STETKAR: The whole point

18 is not to microanalyze individual events. The point

19 is to kind of probe these assertions about what is the

20 operating experience, what do we learn from that. And

21 if there are assertions that things are getting

22 better, do we actually have quantitative evidence to

sort of support that notion? Because 10-4 23 is still a

24 small number. And one or two events in 25 or 30 years

25 might throw into question our confidence in that very
292

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 small number.

2 MR. SHENG: Yes. As I said, we made a

3 decision based on qualitative judgment. I think that

4 regardless of whether you have nuclear unit or non5 nuclear unit the intents of design and materials I

6 think it would be reflected in both sides of the

7 turbines.

8 However, the only thing that we emphasize

9 that we didn't use a large database, but use a smaller

10 database purely because we believe that there are lot

11 of things which have been changed in the nuclear

12 operating practices, maintenance, as I said, the

13 testing frequencies and the requirement of the quality

14 of the EHC oil and all these things and the

15 inspections and all these things that we think that

16 the nuclear units are better maintained. That's why

17 we better use -- It is as I said based on qualitative

18 judgment.

19 MEMBER-AT-LARGE STETKAR: Okay.

20 MR. SHENG: And based on that qualitative

21 judgment that we think the operating experience is

22 consistent with the turbine failure rate of 1E-4 per

23 turbine year and also result we maintain the current

24 criteria of P1 and P4. We did not change it. We

25 changed it slightly. I'm going to elaborate on later
293

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 slides.

2 MR. JONES: Also I think it's important to

3 point out what we're really saying is operating

4 experience supports probabilistic type of analyses

5 performed by the turbine vendors that estimate that

6 turbine destructive overspeed frequencies are lower

7 than that number.

8 MEMBER-AT-LARGE STETKAR: I can also turn

9 that around and say limited operating experience does

10 not refute those analyses.

11 MR. JONES: Right. That's a better way.

12 MR. SHENG: Now slide 11. Now let's shift

13 gears to the risk-informed approach and this RG allows

14 applications conforming to RG 1.174 be considered on

15 a case-by-case basis and directly addressing ACRS

16 Comment 3. So in the previous version of the RG, we

17 kind of had an active tone about using the risk18 informed approach. But considering your comments that

19 we think we would like to entertain that the risk20 informed approach.

21 However, one of your comments also said

22 that whether the risk goal should be redefined for new

23 reactors. And after a lot of internal debate and

24 discussions and reviewing several revisions of the

25 language finally we decide to say the risk goal is not
294

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 defined for turbine missiles for new reactors.

2 However, currently we'll use the SECY Paper 10-0121

3 entitled "Modifying The Risk-Informed Regulatory

4 Guidance for New Reactors" to compare to our review.

5 MEMBER-AT-LARGE STETKAR: I understand the

6 rationale and that's hopefully as best as we can hope

7 in the context of this reg. guide.

8 MR. SHENG: Yes. It's simply because I

9 think the responsible branch did not want their hands

10 to be tied. They wanted more freedom to do the

11 review.

12 CHAIRMAN ABDEL-KHALIK: But just back to

13 the point of nuclear experience versus fossil

14 experience, do we have any idea how many turbine

15 overspeed have occurred in fossil plants over the past

16 ten years?

17 MR. SHENG: No. I did not do the

18 investigation. So I did not know.

19 CHAIRMAN ABDEL-KHALIK: So you have no

20 idea about whether the probability or the experience

21 base for the fossil side of it is any different than

22 the nuclear experience.

23 MR. SHENG: Right.

24 CHAIRMAN ABDEL-KHALIK: So I'm not sure

25 why the argument that we should limit the database to
295

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 only data from nuclear operations.

2 MR. SHENG: Yes. As I explained before,

3 it's based on our qualitative --

4 CHAIRMAN ABDEL-KHALIK: It would seem to

5 me that the investment protection on the part of the

6 people in the fossil business would drive them towards

7 equally high standards.

8 MR. SHENG: However if you do increase the

9 testing frequency or maintain a certain quality of the

10 control system that it would require money. For

11 instance, like one nuclear unit, right, they even

12 refused to adopt the insurer's recommendation after

13 this Salem 2 event.

14 The nuclear operating -- nuclear insurance

15 company issued guidance that says you have to follow.

16 But one unit refused to follow and then paid higher

17 premium because they think their system is fine.

18 Certain, not all guidelines, guidelines.

19 So all I'm saying is that I do believe

20 that once we issue so many guidelines. Right. And

21 the nuclear units followed. And they don't follow

22 them completely. So if the non-nuclear plants were

23 not affording the effort and they will follow all

24 these guidelines rigorously, that I just don't -- I

25 find it hard to believe. That's why the reason that
296

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 based on the quality assessment.

2 CHAIRMAN ABDEL-KHALIK: But absent data

3 this is all conjecture.

4 MR. SHENG: I understand.

5 CHAIRMAN ABDEL-KHALIK: It is quite

6 possible that when you actually collect the data

7 you'll find that the failure rates are the same and

8 maybe you're doing too much testing that is not

9 necessary because it doesn't impact the failure rate.

10 MR. SHENG: Right.

11 MR. JONES: We do have earlier operating

12 experience that did indicate problems with inadequate

13 testing especially if the individual components were

14 not individually tested. There was a problem missing

15 existing failed components and then having a

16 subsequent failure that resulted in negative impacts.

17 And that contributed to the Salem 2 overspeed event.

18 So I think that particular piece of

19 operating experience we know is infiltrated in the

20 operating practices of the nuclear units. And that

21 has a big effect on that. But I understand your point

22 regarding fossil units may indicate we're --

23 MEMBER-AT-LARGE STETKAR: Or international

24 nuclear units. I mean if the notion is that nuclear

25 people do better on these things because they do
297

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 better on these things --

2 MEMBER SIEBER: Safety culture issue.

3 MR. JONES: Right. A lot of that is.

4 MEMBER-AT-LARGE STETKAR: Anyway I think

5 we talked about the frequency.

6 MEMBER SIEBER: There are differences

7 between coal-fired and nuclear units. For example,

8 coal-fired plants generally have two pole generators.

9 So they turn at 3600 rpm compared to 1800 rpm per

10 nuclear.

11 Nuclear units have longer blades. And

12 that's because somebody said lousy steam. That lousy

13 steam is the right answer to that. You've got to get

14 every piece of horsepower out of it and the way to do

15 is high moisture content on the tailend, large blades,

16 do as much expansion as you can.

17 The performance records that I'm aware of

18 are probably worse for fossil units at least in the

19 companies that I've worked for in the past. And

20 because the insurance company will make them do an

21 overspeed check but there's multiple paths to get the

22 trip and the one they paid most attention to was the

23 moving slug in the trip. And so they would not test

24 all the methods.

25 I think there's something to be learned
298

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 from fossil units. But I'm not sure I would rely on

2 their record. Just establish the probability of

3 failure.

4 MEMBER-AT-LARGE STETKAR: Without

5 speculating on what the data might show, I think that

6 when you collect the operating record -- I mean we're

7 hopefully not looking at 10,000 turbine failures. If

8 you're looking at a couple of hundred failures and

9 examine the root causes for them and I'm sure that

10 that documentation is available because these types of

11 events actually catch your interest and people are

12 probably interested in looking at the causes. If you

13 compare the causes of those to the designs and testing

14 and maintenance that's performed on the nuclear units

15 you might have justification to say "Well, that

16 particular type of event is not applicable to a

17 nuclear unit turbine for the following reasons." Or

18 you might find that it might be applicable.

19 But until you actually have the operating

20 experience in front of you and you can examine the

21 event records, a lot of it is just speculation. It

22 might be better. It might be worse. We just don't

23 know. And if we're trying to predict numbers that

24 were one in 100 that's a little bit different. We're

25 trying to predict numbers that are a magnitude lower
299

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 than one in 100.

2 MR. HONCHARIK: But I guess also I think

3 -- I understand. Yes. To see whether or not some of

4 the fossil plant failures can be applicable to

5 nuclear. But also with the I guess to see whether or

6 not the frequency is the same, that would need to have

7 not only what the failures are but what the operating

8 experience years and everything for each of the units.

9 MEMBER-AT-LARGE STETKAR: In many of these

10 cases, the desire to be precise to six significant

11 figures is less important than to be accurate to

12 within an order of magnitude or so.

13 MR. HONCHARIK: Right.

14 MEMBER-AT-LARGE STETKAR: So having a

15 precise estimate of the number of turbine operating

16 hours might be less important than to say we took data

17 from the following set of large units and we know

18 roughly that each of those units has operated X number

19 of years. That information should be readily

20 available.

21 MR. HONCHARIK: That's if they haven't

22 replaced rotor blades.

23 MEMBER-AT-LARGE STETKAR: Accuracy is

24 good. Precision is not necessarily required for these

25 types of -- After all, this is not a precise data
300

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 assessment. It's an evaluation of operating

experience to derive confidence that indeed these 10-4 2

3 numbers are not contrary to actual experience. And as

4 you said people who do analyses calculate those

5 numbers. But maybe they're missing something in their

6 analysis also that they haven't thought about.

7 We've beaten the number I think to death

8 here. Simon, I think you can go on.

9 MR. SHENG: Yes. Let's move onto slide 12

10 and here I want to summarize the enhancements in the

11 proposed RG 1.115. The first is that we provide the

12 guidance for high-trajectory missiles. And then we

13 define SSCs to be protected. We clarify the current

14 NRC emphasis on P1 and permit the approach of

15 considering P1, P2 and P3. And we validate operating

16 experience since 1977. Slide 13.

17 And in regards of provide high-trajectory

18 missiles, we did -- Basically I think we can neglect

19 this one. The only thing I want to mention is that in

20 the equation you can see that the P 10 which is the

21 probability of overspeed protection system protection

22 system failure. And this is a significant contributor

23 to the entire P1.

24 And the first P 1p which P1f is the

25 probability of disk failure based on Probabilistic
301

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Fracture Mechanics considering stress corrosion

2 cracking. So you did all these kind of fancy analysis

3 to a general number. But in the end your probably

4 overspeed system failure really is a big number

5 compared to that. They are comparable, but you can't

6 ignore either of those.

7 MEMBER-AT-LARGE STETKAR: Simon, just one

8 question about this regulatory position 2B does

9 discuss high-trajectory missiles and in particular it

10 says "As the preferred option for unfavorably oriented

11 turbines limiting the turbine missile generation..."

12 MR. SHENG: Excuse me. You're talking

13 about slide 14. Right?

14 MEMBER-AT-LARGE STETKAR: Yes. Okay. I'm

15 sorry. I'll let you go to 14. I'm sorry. I didn't

16 read far enough ahead.

17 MR. SHENG: Slide 14 that we clarified --

18 Slide 14. Yes. We clarified the current emphasis on

19 P1 and we provide guidance for the favorably oriented

20 turbines and for the low trajectory and high

21 trajectory. 

22 Mr. Stetkar, you can raise your question.

23 MEMBER-AT-LARGE STETKAR: I'm sorry for

24 breaking in. I didn't read far enough ahead in the

25 slides. The concern and I think we voiced this at the
302

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Subcommittee meeting is that the actual words say "As

2 the preferred option for unfavorably oriented

3 turbines," the lower part of your slide 14 here.

4 MR. SHENG: Okay.

5 MEMBER-AT-LARGE STETKAR: "Limiting the

6 turbine missile generation frequency P1 for trajectory

missile to a value of less than 1 times 10 -5 7 per

8 year."

9 MR. SHENG: Right.

10 MEMBER-AT-LARGE STETKAR: "The evaluation

11 for high-trajectory turbine missiles is not needed

12 because the turbine missile generation frequency for

13 low-trajectory missiles is bounding."

14 MR. SHENG: Right.

15 MEMBER-AT-LARGE STETKAR: And I think we

16 raised the question of why is the turbine missile

17 generation frequency for high-trajectory missiles

18 different and bounded by the turbine missile

19 generation frequency for low-trajectory missiles. The

20 frequency P1 as you noted on the previous slide is

21 driven primarily by failures of the overspeed system.

22 So it's not --

23 MR. JONES: We shouldn't say bounding.

24 It's more restrictive.

25 MEMBER-AT-LARGE STETKAR: It's -- I don't
303

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 want to put words in your mouth. But I think during

2 the Subcommittee meeting we had a discussion that said

3 the combined likelihood of missile generation

4 frequency times P2 times P3 may be bounded by the

5 combination of those three factors for low-trajectory

6 missiles.

7 MR. JONES: Right.

8 MEMBER-AT-LARGE STETKAR: And yet the

9 guidance in the regulatory guide still focuses on

10 simply a frequency argument which doesn't seem to make

11 any sense. It seems that the frequency of high12 trajectory missiles would be the same as the frequency

13 of low-trajectory missiles. If I parse my turbine up

14 into four equal circumferential segments or something

15 like that, it might be a half if I don't care about

16 missiles that go down through the main condenser.

17 But just to say that the frequency of the

18 turbine missiles, you don't need to do it because P 1

19 for low-trajectory missiles bounds P1 for high20 trajectory missiles doesn't seem the right notion.

21 MR. JONES: I think the intention is to

22 say that that's a more limiting criterion for

23 acceptability. And that's based in part on the P 2

24 portion of that.

25 MEMBER-AT-LARGE STETKAR: And I think in
304

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 the sense that the last time that this reg. guide was

2 updated was 34 years ago. Sometimes the intent of the

3 justification is important to document because people

4 will make inferences from the words. And if the

5 intent is to say that the combined damage from high6 trajectory missiles, there's reason to believe in some

7 basis for that, is bounded by the low-trajectory

8 missiles, then it would seem to make sense to

9 elaborate a bit on that because otherwise people will

10 just say that NRC accepts the fact that I don't need

11 to look at high-trajectory missiles because I know for

12 some reason the NRC says that the frequency is less.

13 And it's not a strict ejection frequency argument.

14 It's the overall damage.

15 MR. JONES: I guess there is a -- For a

16 typical plant arrangement, there is a slightly lower

17 number for high-trajectory missiles that could still

18 land on the sight footprint compared to low-trajectory

19 missiles. There's a lot broader band exit direction,

20 if you will, that will hit or strike an essential

21 component for a direct path as opposed to a lob.

22 MEMBER-AT-LARGE STETKAR: The product of

23 P2 times P3 is less.

24 MR. SHENG: Well, P2 I think particularly.

25 MR. JONES: Right.
305

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. SHENG: P2 yes. I think the language

2 is there. Okay. Maybe modified a little bit because

3 when we say responding actually if you read it

4 literally that means that we're talking about P1 only.

5 MEMBER-AT-LARGE STETKAR: That's right.

6 MR. SHENG: But here the implication is

7 that we are actually considering the P2 of the high8 trajectory missile and we did not say so clearly in

9 our argument.

10 MEMBER-AT-LARGE STETKAR: That's right.

11 That's the whole point of the comment.

12 MR. SHENG: Right.

13 MEMBER-AT-LARGE STETKAR: Because one of

14 the -- The reason -- You know it sounds like a minor

15 point. But the reason is to increase the notion that

16 not only P 1 but P2 and P3 are factored into both

17 regulatory, the scope of regulatory reviews and

18 decisions that you might make about the potential risk

19 from turbine missiles.

20 MR. SHENG: I made a note that we need to

21 modify the language.

22 MEMBER-AT-LARGE STETKAR: This is a case

23 where you're actually making arguments with regard to

24 P2 and P3.

25 MR. SHENG: Right.
306

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER-AT-LARGE STETKAR: P 2 let's say

2 about why the staff believes it's not necessary to

3 look at high-trajectory missiles in this case. It

4 should be just elaborated a bit.

5 MR. SHENG: Yes. Your point is well6 taken.

7 MEMBER-AT-LARGE STETKAR: Because it sort

8 of fits the mold of where you're eventually going into

9 something that you may get to in these slides.

10 MR. SHENG: Right. And we can go directly

11 to slide 16. As I said, the current NRC approach is

12 emphasis on P1 and as a result all the plant-specific

13 applications is focused on P1. But now that this RG

14 actually permits the approach of considering P 1, P2,

15 and P3. So as long as your P1 times P2 and P3 is less

than 1E-7 16 then we will consider it.

17 The features of these applications that we

retain the RG 1.115 criterion of 1E-7 18 for the

19 probability of failure of an essential system caused

20 by low-trajectory missiles. And by doing so, we also

21 relax -- To address the point of your earlier comment,

22 we relax the current P1 criterion for an unfavorably

23 oriented turbine from 1E-5 to 1E-4 when P 2 and P3 are

24 also considered. So basically I think if the

25 applicant has a way to control the P 2 to a small
307

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 number then we can relax a little bit on the P1.

2 MEMBER-AT-LARGE STETKAR: And we had some

3 discussion about this also in the Subcommittee

4 meeting. If ultimately the criterion is a frequency

of damage to risk important SSCs of less than 1E-7 5 per

6 year if I'm an applicant and I can provide an analysis

7 that gives the staff reasonable assurance that the

product of P2 times P3 is less than 10-6 8 why do I also

9 need a turbine missile ejection frequency that must be

less than 1E-4 10 ? In other words, why do the criteria

11 that are imposed under this particular regulatory

12 position 2C require both the product of the missile

ejection frequency to be less than 10-4 13 and the

14 product of our ultimate protection frequency to be

less than 10-7 15 ? Why isn't it just a total less than

10-7 16 if I provide a detailed evaluation of my plant

17 specific geometry and analyses to quantify P2 and P3

18 rather than just taking the accepted regulatory

19 guidance values for those two parameters?

20 MR. SHENG: Right. Theoretically you are

21 correct. However I believe that even we do so, okay,

22 the licensee probably will not do that because that

means the turbine design according to the P1 or 10-2 23 .

24 That means their turbines is going to fail much more

25 frequently. And it will cause a lot of cost on their
308

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 side.

2 MEMBER-AT-LARGE STETKAR: Okay. But you

3 know I take risk with my money. I got to Las Vegas.

4 I invest my money. I lose it. That's my investment

5 risk that is not risk to public health and safety from

6 the damage to nuclear safety related equipment.

7 MR. SHENG: I understand.

8 MEMBER-AT-LARGE STETKAR: I would argue

that if indeed that 1E-4 9 addresses utility investment

10 risk that's not something traditionally that the

11 agency tries to regulate.

12 MR. SHENG: I understand that. As I said,

13 we already -- In the second bullet basically we

14 already increased the criteria by an order of

15 magnitude. And we would like to see more as I said

16 operating experience to get an even bigger number of

17 the criteria for P1.

18 But right now it's just how far we want to

19 go at the moment. And as I said that if a licensee

20 have a different approach using a very small P1 number

21 at their own risk, then we'll consider that at that

22 time.

23 MEMBER-AT-LARGE STETKAR: But when you say

24 very small, you mean very large.

25 MR. SHENG: Yes, very large.
309

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER-AT-LARGE STETKAR: That still

2 though in the regulatory guidance and in not only the

3 text of position 2C but also the numerics in Table 1,

4 it tells me as applicant or a licensee that you will

not consider a P1 that is greater than 1E-4 5 despite the

6 fact that my product -- You allow me do a detailed

7 analysis of the product P2 and P3. But if I can show

that that product is P2 times P3 is 10-4 8 let's say.

9 MR. SHENG: Right.

10 MEMBER-AT-LARGE STETKAR: And I therefore

can justify a P1 of 10-3 11 you won't consider that.

12 That's what the regulatory guidance says.

13 CHAIRMAN ABDEL-KHALIK: But doesn't P1 in

14 and of itself impact worker safety?

15 MEMBER SHACK: Yeah, I mean I think

16 there's a defense-in-depth argument here. We really

17 don't like turbines coming apart.

18 MEMBER POWERS: Have you ever seen it

19 happen, Bill? It's so much fun.

20 MEMBER-AT-LARGE STETKAR: We also don't

21 like LOCAs, but we accept certain frequencies of core

22 damage from LOCAs.

23 MEMBER SHACK: But it's a readily

24 achievable goal by modern turbine standards. I think

25 it would be criminal to relax it would be sort of my
310

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 reaction.

2 MR. HONCHARIK: And I guess -- I wasn't

3 here way back when they were doing these P2 - P3. But

4 I think previous to the Hope Creek some were using

5 that P2 - P3 criteria and there are many different ways

6 of doing it. There are very different opinions on the

7 assumptions and such that there is such a wide

8 spectrum that it was very difficult to handle. And I

9 think that's why in '86 they went to P1 criteria.

10 I think that also needs to be taken into

11 consideration of whether or not -- how reliable are

12 those P2 - P3 calculations.

13 MEMBER-AT-LARGE STETKAR: I think there

14 are obviously differences of opinion. This is a

15 change to the regulatory guidance. This says that the

16 regulatory guidance now says the Staff will consider

17 analyses that does a refined evaluation of P2 and P3.

18 But it very, very narrowly restricts that evaluation.

19 And regardless of the ability of a

20 particular licensee to provide an analysis that gives

21 the Staff assurance that their analysis of P 2 and P3

22 is reasonable that they've looked at all of the

23 parameters and done a reasonable analysis, the

24 question is should we presume -- Suppose they have the

25 ability to do a perfect analysis and justify a P 2
311

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

times P3 product of 2E-4. So I could have a 5E-3 1 , 2E --

2 I can't do the math in my head right now. But you get

the notion that I could have a 2E-4 3 turbine missile

4 generation frequency. This says the Staff won't

5 consider that even with a perfect analysis.

6 MR. SHENG: I think this --

7 MEMBER SHACK: That's what we call a

8 hypothetical. Right?

9 MEMBER-AT-LARGE STETKAR: No. People --

10 MEMBER SHACK: Perfect analyses.

11 MEMBER-AT-LARGE STETKAR: Well, I'm not

12 trying to presume. A particular licensee may not

13 adopt this option because they may judge that it's too

14 difficult to do an acceptable analysis of P2 times P3.

15 But that's their judgment.

16 And the question is if they want to try to

17 do that analysis and get the Staff to accept it and

18 believe by doing that analysis they could get a factor

19 of relaxation in their P1 why ought they be restricted

20 from trying that?

21 MR. LABINSKY: If I could address that to

22 some extent. John Labinsky. As you said, the

23 examples you brought up, I think you started with the

24 Staff would not even address that or not even consider

25 that. You know we are talking about reg. guide. 
312

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 Under the regulations, someone could come with an

2 exemption that we wouldn't ever consider.

3 In this case, if someone were to come in

4 under an extreme circumstance, we would look at this

5 as our initial guidance in doing that review. We

6 would look at the guidance that we've used for

7 addressing P2 and P3 and doing that evaluation. And if

8 we felt that it had the credibility and had the

9 sophistication, we would consider that clearly on a

10 case-by-case basis. And that would be the entire reg.

11 guide. But we don't want to put out there that that's

12 something that we would want people to get margin by

13 looking at those numbers and trying to get away from

E-4 14 for the initial turbine failure.

15 Because again we do think having that

16 defense-in-depth and the initial turbine failure

17 being very low is important. So we do want to put out

18 there that we believe that's our initial position. If

19 someone can really prove that to us in P 2 and P3 we

20 would have to look at that on a case-by-case basis.

21 But we've not -- I don't think we'd want to put that

22 into the reg. guide at this point. Let someone else

23 come and ask us that when the situation presents

24 itself.

25 MR. SHENG: Thank you. Okay. Slide 17.
313

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 And I want to review the industry comments

2 that basically the proposed RG considers the pathway

3 for high trajectory missile, provide a way to do that.

4 And robust rotor designs. New rotor designs within

5 current regulatory process. Credit for existing

6 structures as missiles barriers. Sites with multiple

7 units. Applications -- Up to the above it can be

8 reflected either in P1 or P2 calculation because this

9 reg. guide allows them to do the complete approach of

10 using P1, P2 and P3. So you can reflect all this in

11 your calculation.

12 And then also that by taking the

13 Committee's comment we now entertain application

14 conforming to RG 1.174 on a case-by-case basis and

15 also that is also defended by the industry.

16 And another one that we made the

17 commitment to make changes in SRP consistent with the

18 changes we made in the reg. guide.

19 And the last one that we did not do

20 because the industry wanted us to basically lower the

21 P1 as Mr. Stetkar just mentioned to make the criteria

22 more generous. As I said, we think the current

operating history is consistent with 10-4 23 failure

24 rate. So we did not revise RG in that regards.

25 So this is the set of the industry
314

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 comments. However, the resolution resolved all that.

2 It reflected the position we've taken the most recent

3 RG incorporated in ACRS Committee's comments. Next

4 slide.

5 It's the additional industry comments and

6 soliciting comments again is required because the RG

7 Revision incorporated ACRS comments which is rather

8 significant. So we sent it out for additional

9 comments with a shorter response time.

10 And the industry -- Most of the industry's

11 comments involve definitions and wordings changes and

12 we did it accordingly. And one of the comments is the

13 review of risk-informed approach on a case-by-case

14 basis to include generic application. And although

15 the plant-specific, risk-informed approach is more

16 practical, the Staff's consideration of a risk17 informed approach on a case-by-case basis does not

18 rule out generic application if the industry can find

19 that to be very useful to plants.

20 MEMBER-AT-LARGE STETKAR: That came from

21 one of the user groups. Right?

22 MR. SHENG: Right.

23 MEMBER-AT-LARGE STETKAR: They wanted to

24 --

25 MR. SHENG: Basically from EPI.
315

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER-AT-LARGE STETKAR: Yes.

2 MR. SHENG: Okay. So I'm going to present

3 you the slide 19 which is our conclusion. And the

4 proposed RG 1.115 becomes self-contained, providing

5 preferred and acceptable approaches and acceptance

6 criteria against the low-trajectory missiles and high7 trajectory missiles.

8 And the proposed RG 1.115 is consistent

9 with the current criteria emphasizing P1.

10 It also considers the approach using P1,

11 P2, and P3.

12 It considers risk-informed approach on a

13 case-by-case basis.

14 It has considered 2010 and 2011 industry

15 comments.

16 It has fully addressed the six of seven

17 ACRS comments. And the one that we didn't do now is

18 that we are considering how and when to explore the

19 means to provide detailed technical guidelines in the

20 RG. So we're considering it. And this concludes our

21 presentation. Thank you.

22 MEMBER-AT-LARGE STETKAR: Thank you very

23 much.

24 Any comments? Questions from other

25 members?
316

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER SKILLMAN: I do.

2 MEMBER-AT-LARGE STETKAR: Mr. Skillman.

3 MEMBER SKILLMAN: Yes. In the systems

4 that are protected, fire protection is not listed.

5 One can infer it's among the systems. But I ask why

6 that doesn't show up in your revised reg. guide.

7 Where is fire protection in your list here? You've

8 got 16 items. You've got to do a lot of translation

9 to find it in there and you really need to know what

10 you're talking about in terms of the pumping in a

11 plant. Where is it please? Your SSCs?

12 MR. JONES: It's not listed among the

13 SSCs. They're required to be protected because it's

14 not typically accredited for station shutdown. But I

15 understand what you're getting at.

16 MEMBER SKILLMAN: Let me ask another

17 question. In a PWR I could pretty much be sold on a

18 change to P1. I recognize on a B the turbine missile

19 violates reactor coolant system boundary. And so the

notion of going from 10 -5 to 10-4 20 brings with it at

21 least in my mind the same comment that William Shack

22 had. It's almost unthinkable to reduce that number

23 because at least in a B the turbine casing is part of

24 your reactor coolant system pressure boundary.

25 If you have a slight leak, if you're
317

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 running a couple of microcuries per cc of failed fuel,

2 you now have a breather. You now have a release. So

3 I'm wondering if the notion of allowing a reduction of

4 P1 is as prudent as one might think it is particularly

5 for B and maybe the requirement for B may be different

6 than for a pressurized water reactor.

7 And I'm a latecomer. Maybe all of this is

8 processed information. I'm going to stop right here.

9 Thank you.

10 MR. SHENG: We'll consider that.

11 MEMBER SKILLMAN: Thank you.

12 MEMBER-AT-LARGE STETKAR: Any other

13 comments from Members? Questions?

14 (No verbal response.)

15 Are there any members of the public that

16 have any comments or questions?

17 MR. DUBE: Don Dube, Office of New

18 Reactors. John asked the question earlier of whether

less than 10-7 19 could be considered negligible for new

20 reactors in light of the fact that some plants have

21 internal events, core damage frequency, of the order

of 2 X 10-8 22 . That is true, but when one adds up

23 external events, low power shutdown and external

24 events during low power shutdown even though the

lowest plant which is the ESBWR is above 10 -7 25 . And
318

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 that does not include seismic which everyone keeps

2 reminding me is probably the dominant contributor.

3 And while no one has submitted an

4 application yet where they have combine that seismic

5 hazard curve with fragilities to estimate seismically

6 induced core damage frequency, we have done some back

7 of the envelope calculations which indicated it would

be mid 10-7 to mid 10-6 8 range probably depending on the

9 site.

10 So qualitatively I'd feel comfortable

11 saying that if you could get the probability of damage

to an essential system less than 10 -7 12 recognizing

13 there is some reduction and margin to that from core

14 damage it's pretty close to be negligible in my

15 opinion.

16 MEMBER-AT-LARGE STETKAR: Thanks, Don.

17 That helps put some perspective on those numbers.

18 Anything else? Anyone?

19 (No verbal response.)

20 If not, thank you all very much. I think

21 it was a good presentation. We had a good discussion

22 and I very, very appreciate all the effort you put

23 into making the changes to the reg. guide since the

24 Subcommittee meeting. It's been very responsive. I'm

25 pretty happy with it.
319

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 So thank you. And with that, Mr.

2 Chairman, it's back to you with seven minutes to

3 share.

4 CHAIRMAN ABDEL-KHALIK: Thank you. The

5 next item on the agenda is preparation of ACRS

6 reports. But before we get to that I think

7 Westinghouse may be ready to present the answer to the

8 question that was posed during the previous session.

9 MEMBER RAY: Now we did go next door and

10 debate a little bit about what question we were

11 asking. So let me tell you what I told them. I hope

12 it's satisfactory. It is that we're looking to judge

13 the sensitivity of containment pressure to whatever

14 measure of air temperature we have. And that's an

15 ambient temperature I expect. We'll see here in a

16 second.

17 They do have, of course, a profile of the

18 temperature through the wall of the structure. But

19 that doesn't really go to the question of effect on

20 peak pressure which we may be able to infer from the

21 information they have for us.

22 CHAIRMAN ABDEL-KHALIK: Thank you.

23 MR. CORLETTI: And I think as Harold said

24 we heard the questions and I think we're going to try

25 to present two aspects of it.
320

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 As we're preparing to get the slides up

2 there, I think what we were hearing is what would be

3 the effect of solar radiation or solar heat gain on

4 the peak containment pressure analysis and we wanted

5 to look at the effects of that effect of solar gain on

6 the inlet air temperature. What might it be? So we

7 looked at two aspects of how could that raise the air

8 temperature.

9 One was we looked at the grating across

10 the structure so that once the air had entered the

11 shield building structure as it would travel down

12 between the shield building all and the baffle.

13 That's the first point.

14 And then the second point is we have done

15 parametric studies. We have previously done

16 parametric studies that just parametrically if the

17 inlet air temperature is increased so many degrees

18 what's the impact on the peak pressure.

19 The first slide you see there are the

20 results from the calculations that we showed for our

21 evaluation of solar gain. And for that what you see

22 is when the temperature on the outside surface is 129

23 -- 128.5 is the exact number -- the inside wall

24 temperature because this is a transient effect does

25 not increase. It's 0.001 the inside wall temperature
321

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 increases.

2 So essentially there's no heat into the

3 air flowing between the baffle and the shield building

4 wall because effective solar radiation is serving to

5 heat up the concrete. And it's not of a duration.

6 It's not a steady state problem where you've developed

7 a grating across that structure. So really this is

8 showing you the temperature gradient across the

9 structure, across the shield building wall, in that

10 condition when it's 128.5 degrees. That was one

11 aspect.

12 I'm going to turn it over to Rick now.

13 He's going to basically try to put -- If you put that

14 aside, if we just look at parametrically the air inlet

15 temperature -- Should I pause there?

16 VICE CHAIRMAN ARMIJO: Can you just go

17 back again?

18 MR. CORLETTI: Sure. 

19 VICE CHAIRMAN ARMIJO: I want to look at

20 that.

21 MR. CORLETTI: Do you want me to keep

22 going?

23 MEMBER RAY: I'd really like you to do

24 that. But, of course, if Sam has a question.

25 VICE CHAIRMAN ARMIJO: Yes. I just want
322

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 to --

2 MEMBER RAY: I'm just afraid that we'll

3 lose the parametric. But go ahead, Sam. Ask your

4 question.

5 VICE CHAIRMAN ARMIJO: Just go back to

6 that curve. I just want to make sure I understand it.

7 You say that will be a steady state temperature

8 gradient across the wall.

9 MR. CORLETTI: No.

10 MEMBER SHACK: It's the thermal history

11 that you have for this. What temperature do you start

12 with --

13 VICE CHAIRMAN ARMIJO: I'm having a hard

14 time -- 

15 MEMBER SHACK: -- when you raised it to

16 115?

17 MR. CORLETTI: I believe we start -- Go

18 ahead, Tod.

19 MR. BAKER: I'm sorry. We started at 115

20 degrees.

21 MR. CORLETTI: And then we turn on the

22 sun.

23 MEMBER RAY: You turn on the sun and so it

24 gets hotter on the outside.

25 MEMBER SHACK: Okay.
323

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MR. BAKER: We started it at a steady

2 state of 115 degrees.

3 MEMBER SHACK: And then just let the sun

4 shine.

5 MR. BAKER: And we added the sun. Yes.

6 MEMBER SHACK: And after 16 hours you get

7 to this.

8 MR. BAKER: Right. The sun is moving

9 around the building.

10 MR. CORLETTI: I think we said at 4:45

11 p.m. was the maximum temperature in the west facing

12 wall of the structure assuming the plant width is the

13 way the plant is actually oriented.

14 VICE CHAIRMAN ARMIJO: Okay. I

15 understand.

16 MR. OFSTUN: Can I ask a question? Did

17 you guys run that for 24 hours and did you show the

18 cooldown effect afterwards?

19 VICE CHAIRMAN ARMIJO: This is just taking

20 it to the peak temperature. Right?

21 MR. OFSTUN: Yes.

22 VICE CHAIRMAN ARMIJO: And then you stop.

23 MR. OFSTUN: I just wanted to see if at

24 the end.

25 MR. BAKER: We actually ran it for 24
324

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 hours at an ambient temperature of 115 degrees and

2 with the sun the way the sun would go.

3 MR. OFSTUN: Did it get back down to 115

4 at the end of the day?

5 MR. BAKER: Roughly.

6 MR. OFSTUN: Okay.

7 VICE CHAIRMAN ARMIJO: Okay. I understand

8 what the chart says.

9 MR. CORLETTI: So the next slide I think

10 we're going to let Rick present is the parametrics.

11 Set that aside. Parametrically if you increase the

12 air inlet temperature what the impact might be.

13 MR. OFSTUN: Right. The first bullet here

14 was what Mike just described that there's a very small

15 amount of temperature rise on the inside surface of

16 the shield.

17 MEMBER POWERS: How thick is that concrete

18 wall again?

19 MR. OFSTUN: Three feet thick.

20 So we did just a rough estimate and

21 assumed that the average incoming air temperature

22 increase by three and a half degrees and we got that

23 by just assuming that the sun was shining on one

24 quadrant essentially full force and raised that

25 quadrant to 129 degrees. And the other three were at
325

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 115. And then the average air temperature going that

2 could -- The maximum average air temperature that

3 could go into the inlets would be 118.5 degrees. And

4 that's how we came up with the 3.5 degree number.

5 MEMBER BROWN: That's the external air.

6 MR. OFSTUN: Yeah.

7 MEMBER BROWN: Before the air comes down

8 and then up.

9 MR. OFSTUN: Yes.

10 MR. CORLETTI: There is no physics behind

11 this.

12 MR. OFSTUN: No.

13 MEMBER RAY: They did what I asked them to

14 do.

15 MR. CORLETTI: -- wrong, but we are

16 conservative I think was his words to us. But if you

17 assume that the air is traversing on the outside of

18 the shield building --

19 MR. OFSTUN: Filling up.

20 MR. CORLETTI: It's filling up into the

21 air intake. Picking up that energy and it reaches the

22 same temperature as the plate. So basically one23 fourth is going in at 129 and the other three-fourths

24 is going at 115. They calculated it could be as much

25 as a 3.5 degree rise.
326

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 (Off the record discussion.)

2 MEMBER RAY: Yes, that's the point is

3 what's the effect.

4 MR. OFSTUN: Yes.

5 MEMBER RAY: I don't know if this is a

6 good idea or bad idea.

7 MR. OFSTUN: We have a sensitivity study

8 that shows for a 10 degree increase in the ambient air

9 temperature the containment peak pressure calculated

10 went up by 0.05 psi. So if you consider a 3.5 degree

11 increase in the ambient air temperature due to solar

12 heating of the external surface and we're not even

13 counting the cooling because as it goes down through

14 the annulus it's going to cool off a little bit. And

15 as it goes up it will heat up on the other side. But

16 we came up with less than 0.02 psi for an increase in

17 the containment pressure.

18 MEMBER SIEBER: Now does the sunshine have

19 an effect on the temperature of the water in the tank?

20 VICE CHAIRMAN ARMIJO: It can be

21 maintained at 40 degrees. Right? 

22 MEMBER RAY: Yes. Again they assume the

23 maximum allowable temperature by tech spec.

24 MR. OFSTUN: It is.

25 MEMBER SIEBER: Okay.
327

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 MEMBER RAY: And if you assume that they

2 can't measure it accurately because of the sun I

3 suppose that would be a problem. But there is so much

4 darn inertia in that water.

5 MEMBER SIEBER: Yes, there's a lot of

6 water up there.

7 MR. CORLETTI: That's right.

8 MEMBER SIEBER: Probably a degree or two.

9 MEMBER RAY: Okay. Do you guys want to

10 say more?

11 MR. CORLETTI: I think we're done.

12 MEMBER RAY: I think the point that at

13 least I was trying to get them to make was what is the

14 sensitivity to a variation in the ambient air

15 temperature for whatever reason, a brushfire or the

16 sun or whatever you want to think about.

17 CHAIRMAN ABDEL-KHALIK: And this

18 parametric calculation is part of the record.

19 MEMBER RAY: It is now. It's going to be

20 part of this record.

21 MR. CORLETTI: Yes. It was a calculation

22 that we did as part of one --

23 MR. OFSTUN: It's part of count note.

24 MR. CORLETTI: A Westinghouse count note.

25 But by putting it on the record here I think we've
328

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS

1323 RHODE ISLAND AVE., N.W.

(202) 234-4433 WASHINGTON, D.C. 20005-3701 (202) 234-4433

1 just -- But we do have a QA record of it back in

2 Cranberry.

3 VICE CHAIRMAN ARMIJO: Was that

4 calculation done specifically for this meeting or had

5 that been done before?

6 MR. OFSTUN: Had been done years before.

7 VICE CHAIRMAN ARMIJO: Okay. Thank you.

8 MEMBER RAY: All right, Mr. Chairman.

9 CHAIRMAN ABDEL-KHALIK: Well, thank you.

10 At this time, I guess we're going to move onto the

11 next item on the agenda.

12 (Chorus of thank yous.)

13 The preparation of ACRS reports. But

14 before we do that, let's take a ten minute break. And

15 when we get back we will be off the record.

16 (Whereupon, at 5:01 p.m., the above17 entitled matter was concluded to adjourn to closed

18 session.)

19

20

21

22

23

24

25
Near-Term Task Force 

Presentation

Advisory Committee for Reactor Safeguards

September 8, 2011
NRC Near-Term Task Force• Leader

– Dr. Charles Miller

• Members

– Amy Cubbage– Dan Dorman– Jack Grobe– Gary Holahan– Nathan Sanfilippo
Near-Term Task Force Summar

• Similar sequence of events in the U.S. is 

unlikely 

• Existing mitigation measures could reduce 

likelihood of core damage and radiologicareleases

• No imminent risk from continued operatio

licensing activities

• Safety enhancements recommended
Summary of Recommendations

• 12 overarching recommendations• Detailed recommendations support 

implementation

– Policy Statement– Rulemakings– Orders– Staff actions– Long-term evaluation
Focus Areas

• Regulatory framework• Defense-in-depth philosophy

– Protection from natural phenomena– Mitigation for long-term station blackou– Emergency preparedness (EP)

• NRC programs
Recommendation 1

Enhance NRC framework for regulating beyond design basis events and severe accidents
Recommendation 2 

Update seismic and flooding ana

and protect plants from these ev
Recommendation 3 

Long Term Evaluation Topic:Evaluate potential enhancemenprevent or mitigate seismically induced fires and internal floods
Recommendation 4 

Strengthen coping for prolonge

station blackout events
Recommendation 5

Require reliable hardened vent designs in BWRs with Mark I anMark II containments
Recommendation 6

Long Term Evaluation Topic:

Identify insights about hydrogen conand mitigation inside containment oother buildings
Recommendation 7 

Enhance spent fuel pool instrumentatmakeup capability
Recommendation 8 

Strengthen and integrate onsite eme

response capabilities

– Emergency Operating Procedures (EOPs)– Severe Accident Management Guidelines (SA– Extensive Damage Mitigation Guidelines (EDM
Recommendation 9

Require that facility emergency planaddress prolonged SBO and multiunevents
Recommendation 10 

Long-Term Evaluation Topic:

Additional EP topics related to multiunit eand prolonged SBO

– Protective equipment for emergency respond– Decisionmaker qualifications– Command and control– Emergency Response Data System (ERDs)
Recommendation 11 

Long-Term Evaluation Topic:

Additional emergency preparedness issu

– Offsite emergency response– EP decisionmaking– Radiation monitoring– Public education on radiation safety and use 

potassium iodide (KI)
Recommendation 12 

Strengthen regulatory oversight of licensee safety performance (ROP) focusing more attention on defensedepth requirements 
Next Steps

Commission SRM issued August 19, 20directed the staff to:

– Draft Charter for NRC’s longer term review (co– Prepare 21-day notation vote paper identifying 

that can and should be initiated without unnecdelay

– Prepare 45-day notation vote paper prioritizing 

Force Recommendations 2 through 12

– Prepare notation vote paper regarding Task F

Recommendation 1 (due in 18 months)
September 2, 2011

Ms. Cindy K. Bladey

Chief, Rules, Announcements and Directives Branch

U.S. Nuclear Regulatory Commission

Washington, DC 20555-0001

Subject: Industry Comments on Proposed Near-Term NRC Actions Associated With the Fukushima 

Dai-Ichi Accident; Docket Number NRC-2011-0196

Project Number: 689

Dear Ms. Bladey,

The Nuclear Energy Institute1appreciates the opportunity to provide comments and input on the set of 

proposed near-term U.S. Nuclear Regulatory Commission (NRC) actions associated with the NRC report, 

Recommendations for Enhancing Reactor Safety in the 21st Century, The Near-Term Task Force Review of 

Insights from the Fukushima Dai-ichi Accident. This letter supplements the industry comments made in the 

NRC August 31, 2011 public meeting and reflects input provided by several industry working groups and 

the chief nuclear officers of all U.S. nuclear operating companies.

Detailed comments on each of the six main recommendations are provided in the attachment to this letter.

In addressing the NRC task force recommendations, we encourage the Commission to adopt a flexible, 

performance-based approach, especially in the area of beyond design bases activities, to allow for the 

variations in siting, geographical and geological locations, and plant designs. 

The industry agrees that there are important lessons to be learned and implemented from the Fukushima 

accident. The industry has developed a strategic plan, The Way Forward, to coordinate and manage its 

response to the Fukushima crisis. The plan emphasizes the importance of maintaining high safety 

 

1

 NEI is the organization responsible for establishing unified nuclear industry policy on matters affecting the nuclear energy 

industry, including the regulatory aspects of generic operational and technical issues. NEI’s members include all utilities licensed to 

operate commercial nuclear power plants in the United States, nuclear plant designers, major architect/engineering firms, fuel 

fabrication facilities, materials licensees, and other organizations and individuals involved in the nuclear energy industry.
Ms. Cindy K. Bladey

September 2, 2011

Page 2

performance at the 104 operating reactors and covers the development and implementation of lessons 

learned from Fukushima, R&D and technical support, international cooperation and support, 

communications, emergency planning and preparedness, training, and regulatory interactions and 

response. 

The industry will soon complete a provisional timeline that reconstructs the progression of events and 

accident conditions at Fukushima. Once the provisional timeline is completed, discussions with Tokyo 

Electric Power Company are necessary to resolve a number of open issues and questions before the 

industry completes its evaluations. Also, that information will be critical in determining the extent to which 

insights related to the events and conditions pertain to U.S. plants and the potential plant enhancements 

that should flow therefrom. There must be a reasoned determination that the correct lessons have been 

learned and that those lessons are appropriately linked to the causal factors of the Fukushima accidents.

The industry, the public and the NRC must have a common understanding of the events and rationale for 

the actions taken at Fukushima before the industry—as required by the NRC and on its own initiative—

implements plant enhancements. To attain this objective, the industry is willing to discuss the timeline with 

NRC staff. This will provide additional confidence in the development and understanding of the bases for 

regulatory actions being required in response to the Fukushima accidents as well as the manner in which 

new requirements are to be satisfied.

The NRC task force concluded that a sequence of events like the Fukushima accident is unlikely to occur in 

the United States and that continued operation and continued licensing activities do not pose an imminent 

risk to public health and safety. A preliminary industry qualitative, risk-informed assessment of the six NRC 

recommendations under consideration reaches the same conclusion. As a result, we do not believe that 

orders are necessary at this time. To the extent the NRC seeks information from all licensees or seeks to 

elicit a response from all licensees on a significant issue, there are regulatory tools such as generic letters 

and bulletins that can achieve those objectives. 

If the NRC determines that it is necessary to impose new requirements on a generic, industry-wide basis, 

the appropriate regulatory process is rulemaking. If necessary, such rulemakings could be expedited. In 

summary, we believe that the NRC and all stakeholders would benefit from the transparent and 

deliberative process mandated by the Administrative Procedure Act. 

The near-term actions should be focused on those enhancements that generally may be attainable within 

12 to 18 months and where additional clarifying information forthcoming from Fukushima will not negate 

earlier decisions.
Ms. Cindy K. Bladey

September 2, 2011

Page 3

To effectively implement the multi-unit staffing proposal in the NRC task force recommendation 9 

concurrent with the existing EP rule change, the implementation schedule for the emergency response 

organization needs to be extended by one year to accommodate the staffing criteria.

The industry is committed to ensuring that the U.S. nuclear industry learns from and incorporates the 

lessons from the Fukushima accidents in a manner that will improve safety and plant performance so that 

the nuclear industry will continue provide additional benefit to the nation’s environment and economy. 

Sincerely,

Adrian Heymer

Attachment 

c: The Honorable Gregory B. Jaczko, Chairman, U.S. Nuclear Regulatory Commission

The Honorable Kristine L. Svinicki, Commissioner, U.S. Nuclear Regulatory Commission

The Honorable William D. Magwood, IV, Commissioner, U.S. Nuclear Regulatory Commission

The Honorable George Apostolakis, Commissioner, U.S. Nuclear Regulatory Commission

The Honorable William C. Ostendorff, Commissioner, U.S. Nuclear Regulatory Commission

Mr. R. William Borchardt, Executive Director for Operations, U.S. Nuclear Regulatory Commission
Attachment

1

Comments on NRC Proposed Near-Term Recommendations from the 

Fukushima Dai-ichi Accident

NRC Task Force Recommendation 2

The Task Force recommends that the NRC require licensees to reevaluate and upgrade as 

necessary the design-basis seismic and flooding protection of SSCs for each operating reactor.

The Task Force recommends that the Commission direct the following actions to ensure 

adequate protection from natural phenomena, consistent with the current state of knowledge 

and analytical methods. These should be undertaken to prevent fuel damage and to ensure 

containment and spent fuel pool integrity:

2.1 Order licensees to reevaluate the seismic and flooding hazards at their sites against 

current NRC requirements and guidance, and if necessary, update the design basis and 

SSCs important to safety to protect against the updated hazards.

2.2 Initiate rulemaking to require licensees to confirm seismic hazards and flooding hazards 

every 10 years and address any new and significant information. If necessary, update the 

design basis for SSCs important to safety to protect against the updated hazards. 

2.3. Order licensees to perform seismic and flood protection walk-downs to identify and 

address plant-specific vulnerabilities and verify the adequacy of monitoring and 

maintenance for protection features such as watertight barriers and seals in the interim 

period until longer term actions are completed to update the design basis for external 

events.

NEI Comments and Input

The industry believes the initial focus should be on conducting walk-downs (Recommendation 

2.3) to confirm that the plant is protected against the design bases flood and seismic events.

The other recommendations are longer-term actions.

Walk-downs

Seismic: The industry proposes that a sample set of walk-downs should be conducted in 

accordance with procedures covering the walk-down criteria and validation against the design 

bases. In addition, a process for selecting the sample set of systems, structures and 

components should be developed together with criteria for determining when the sample should 

be expanded, if circumstances dictate. Regulatory interactions and endorsement of the walkdown criteria should occur prior to conducting the walk-downs to ensure that there is a 

common understanding on the approach and criteria. It should be recognized that additional 
Attachment

2

time should be allowed for completing the seismic walk-downs because some safety-related 

structures, systems and components may be accessible only during shutdown conditions.

External flooding: A similar approach to the seismic walk-downs would be employed except 

there would be no need to use a sampling methodology. As with the seismic walk-downs, 

regulatory interactions should occur in advance to reach a common understanding on the 

approach and acceptance criteria prior to commencing the activity.

Ten-Year Update of Seismic and Flooding Hazards

NEI believes that a process should be developed for identifying and assessing new and 

significant information as it emerges rather than wait 10 years. Such an approach would be 

consistent with how the NRC and the industry manage other new information. The industry 

recommends a three-phase process approach:

1. Identification of pertinent information that is of sufficient significance to warrant 

assessment.

2. Assessment to determine whether the information would impact the hazard.

3. A process for updating the hazard and determining whether changes are needed. The 

update would be performed against current regulatory requirements and standards 

based on the new assumptions and information. For example, if the original design 

bases standard was a 500-year flood, the update would be based on the 500-year flood,

but the impact of an increased downstream levy height would be evaluated. Similarly, if 

the Corps of Engineers changed the height of the 500-year flood standard based on 

updated or new meteorology information, the impact on the plant would be evaluated 

against the new 500-year flood, even though a new plant may be evaluated against a 

750-year flood.

Re-evaluation of Seismic and Flooding Hazard

Re-evaluations of the seismic and flooding hazard are longer-term activities and should be 

considered as part of the NRC long-term activities.

For seismic, we believe GI-199 and any follow-on activities and changes would address this 

aspect of recommendation 2.1.

For flooding, once a process for assessing new and significant pertinent information has been 

developed and the walk-downs have been completed, along with actions to fix any identified 

deficiencies, an evaluation on whether the flooding hazard has changed and its impact on the 

plant can be evaluated.
Attachment

3

Industry Near-term Recommendation

External Flooding Walk-downs

 In response to a §50.54(f) letter, a licensee would develop procedures, including 

acceptance criteria for conducting external flood protection walk-downs and obtain 

NRC concurrence regarding the acceptability of the walk-down criteria.

Conduct the walk-downs and validate the results against the existing design basis 

and report the results to the NRC within 120 days of NRC approval of the walk-down 

criteria.

Seismic Walk-downs

 In response to a §50.54(f) letter a licensee would develop procedures, including 

acceptance criteria for conducting a sample set of seismic walk-downs on safetyrelated systems, structures and components. Obtain a NRC concurrence regarding 

the approach, including the acceptability of the walk-down criteria and mechanism

for expanding the scope of the structures, systems and components to be walked 

down if deficiencies are identified.

Conduct seismic walk-downs for a sample set of critical safety-related systems, 

structures and components and verify against the seismic design bases. For areas 

that are inaccessible because of power operations, the walk-downs will be conducted 

at the first opportunity. Results will be reported to the NRC within 90 days of the end 

refueling outage of the first complete operating cycle following the issuance of the 

regulatory vehicle.

External Flooding and Seismic Hazard Update (Long-Term Activity)

 Initiate rulemaking to require licensees to confirm seismic hazards and flooding 

hazards as new and significant information is identified. If necessary, update the 

design basis to protect safety-related structures, systems and components against 

the updated hazards.

NOTE: We do not believe there is sufficient information or understanding to be able to establish 

acceptance and implementation criteria for an order or proceed with implementation to enable 

completion within a period of time normally associated with an order.

NRC Task Force Recommendation 4

4.1 Initiate rulemaking to revise 10 CFR 50.63 to require each operating and new

reactor licensee to:

(1) establish a minimum coping time of 8 hours for a loss of all ac power,

(2) establish the equipment, procedures, and training necessary to implement an

“extended loss of all ac” coping time of 72 hours for core and spent fuel pool
Attachment

4

cooling and for reactor coolant system and primary containment integrity as

needed, and

(3) preplan and pre-stage offsite resources to support uninterrupted core and spent

fuel pool cooling, and reactor coolant system and containment integrity as needed,

including the ability to deliver the equipment to the site in the time period allowed

for extended coping, under conditions involving significant degradation of

offsite transportation infrastructure associated with significant natural

disasters.

4.2 Order licensees to provide reasonable protection for equipment currently provided 

pursuant to 10 CFR 50.54(hh)(2) from the effects of design-basis external events

and to add equipment as needed to address multiunit events while other requirements

are being revised and implemented.

NEI Comments and Input

Revision to 50.63

The industry agrees that rulemaking is the correct process for implementing enhancements that 

would enable plants to better mitigate and manage an extended and complete loss of AC power 

event. There would be benefit in an advanced notice of proposed rulemaking to frame the 

scope and objectives of the rule. In addition, key aspects of coping time and access to offsite 

resources should be considered. We believe that such an initial step would help to focus 

stakeholder comments and provide for a more efficient overall implementation of 

recommendation 4.1.

The nature of challenges to AC power supplies by natural phenomena are plant- and sitespecific. For example, external flooding progresses very differently at a river or lake site versus 

a site that has a significant tsunami hazard. Therefore, the identification of appropriate shortand long-term coping strategies can vary from site to site. The approach must assure a degree 

of flexibility to accommodate the variations in site configuration, features and hazards.

The basis for the proposed 72-hour additional coping is unclear. The barriers to logistic offsite 

support during an emergency vary depending on location, local geography and transportation 

infrastructure, the hazard and the extent of the natural phenomena impact on the local and 

surrounding counties. For some plants assistance and reliable AC generation may be able to be 

supplied within 24 or 48 hours, at other sites, under different circumstances it may be longer.

Thus, the approach must assure a degree of flexibility in the implementation to accommodate 

varying extended coping time durations for a complete loss of AC power.

Rulemaking is a long-term activity and should be included under the NRC long-term Fukushima 

activities.
Attachment

5

Multi-Unit §50.54(hh) Requirements

We agree that pre-staging additional contingency equipment to meet §50.54(hh)(2) 

requirements for multi-unit sites would be appropriate. The exact composition of the extra 

equipment at or near the site complemented by additional offsite equipment at pre-staged 

areas needs to be determined. It is important to note that the wide diversity of unit 

configurations, geographic locations, varying risks of natural hazards of different types, etc. 

make this analysis complex. A series of regional public meetings in preparation of the advanced 

notice of proposed rulemaking could be beneficial and would assure that the rulemaking is 

correctly framed.

The industry is evaluating the role that regional support centers could play in these situations. 

Such centers would house contingency equipment, especially for slow, evolving events. Prior to 

requiring a definitive site-specific solution to the 50.54(hh)(2) equipment, the strategies for use 

of pre-staged equipment at regional support centers should be established in the implementing 

guidance for the final rule. Distance from the site, accessibility under external events, and sitemitigation strategies that are, in part, dependent on location and proximity of amenities. Other 

support infrastructure are variables that need to be addressed before reaching a final 

conclusion on the additional equipment to be procured and the location of such equipment. We 

note that other countries are evaluating this approach.

Any requirement to require protection of the contingency equipment against natural 

phenomena events should allow for flexibility in implementation to achieve the objective. In 

view of the beyond design bases scenarios that are central to the events under consideration,

the specifications for the protection criteria should be based on commercial standards and not 

the traditional nuclear special treatment specifications. In addition, depending on the site 

geography, natural phenomena hazards and transportation infrastructure, protection could be 

afforded by locating more than the minimal set of equipment at various locations on or offsite 

at a location where it would still be possible to commission the equipment in the timeframe 

required by the §50.54(hh) requirements. Diversity of location and possibly redundancy could 

be just as effective as housing the equipment in Category 1 structures to ensure the availability 

of equipment.

In the interim, until the issues described above are resolved and the equipment is in place, the 

industry believes that short-term actions could be taken to ensure that adequate equipment is 

in place to support the contingency needs for each unit, and that the equipment has adequate 

protection and accessibility.

At this time, we do not believe that there is sufficient knowledge to define the implementation 

criteria that would be required to accompany an order for the additional §50.54(hh) equipment 

and protection requirements. We believe a bulletin requesting information on how sites would 

address the multi-unit contingency equipment issue would be more appropriate. The industry is 
Attachment

6

willing to work on implementing guidance in parallel with a rulemaking amendment to achieve 

the objective of recommendation 4.2 in the optimum time.

New Plants

The NRC task force recommendations recognize the advances of new plant designs. Yet the 

task force report states that COL applicants would have to address prestaging of any needed 

equipment for beyond 72 hours, and ITAAC should be established to confirm effective 

implementation of minimum and extended coping, as described in the recommendation. It is 

not necessary for prestaging to be addressed in COLs, including those for Vogtle 3/4 and 

Summer 2/3, for which the NRC staff has completed its technical review. There is no basis for 

requiring ESBWR or AP1000 COL applicants to adhere to a different coping strategy than 

existing plants.

Part 52 change processes and other regulatory vehicles exist and should be used for ensuring 

that new plant licensees comply with coping, prestaging or other new requirements. These 

matters may be addressed after design certifications or COLs are issued. ITAAC should not be 

the regulatory vehicle for adjusting the licensing basis.

Industry Near-Term Recommendations

 In response to a NRC bulletin, procure additional equipment, as determined from site 

specific evaluations, sufficient to meet §50.54 (hh)(2) requirements for each unit at a 

nuclear power plant and protect it from natural hazards using commercial standards and 

taking into account the use of regional or offsite support locations, as circumstances 

allow and justify.

Long-Term Activities

 Pursue an advanced notice of proposed rulemaking (ANPR) to revise §50.63 as a first 

step to define the scope and key objectives of the revision and to obtain stakeholder 

input on considerations necessary to address coping time, and offsite resources access 

before crafting a proposed rule and developing its implementing guidance.

 If necessary, amend, through rulemaking, the regulatory §50.54(hh) requirement based 

on the final implementation plans.

NRC Task Force Recommendation 5

The Task Force recommends requiring reliable hardened vent designs in BWR facilities with 

Mark I and Mark II containments.

The Task Force recommends that the Commission direct the staff to take the following actions 

to ensure the effectiveness of hardened vents:
Attachment

7

5.1 Order licensees to include a reliable hardened vent in BWR Mark I and Mark II 

containments.

 This order should include performance objectives for the design of hardened vents 

to ensure reliable operation and ease of use (both opening and closing) during a 

prolonged SBO. 

5.2 Reevaluate the need for hardened vents for other containment designs, considering the 

insights from the Fukushima accident. Depending on the outcome of the reevaluation, 

appropriate regulatory action should be taken for any containment designs requiring 

hardened vents.”

NEI Comments and Input

The industry agrees that accessibility of BWR containment hardened vent valves and the ability 

to manually operate these valves under a loss of AC power condition need to be assessed.

BWR Mark I Plants

One of the conclusions from the industry reconstruction activities of the Fukushima events is 

that there are a number of open issues and questions surrounding the containment venting 

operation at Fukushima Dai-ichi. At this time, action and evaluation of hardened containment 

vent valve operation beyond a determination of accessibility and ability to operate hardened 

containment vent valves under loss of AC power conditions should be reserved until more 

information is known and confirmed about the venting operations at Fukushima.

BWR Mark II Plants

Under NRC Generic Letter 88-20, Supplement 3, BWR Mark II licensees were requested to 

consider the use of hardened vents in assessing heat-removal capabilities during severe 

accidents. As a result of these evaluations, BWR Mark II plants should not be required to reevaluate containment heat removal capabilities until there is more confidence and knowledge of 

the venting operations at Fukushima Dai-ichi. At that time, the industry and NRC staff will be 

better positioned to reach a determination on whether additional BWR Mark II heat-removal 

evaluations are necessary.

Other Containment Structures

For other nuclear power plant containment structures, no additional evaluations should be 

performed until there is more definitive information on the Fukushima events that is applicable 

and relevant to these other containment structures. Once this information is available, probably 

towards the end of the year, a determination can be made on whether evaluations and 

modifications are necessary.
Attachment

8

Industry Near-Term Recommendations

 Issue a §50.54(f) letter to require licensees to review plant procedures and guidelines 

for operating existing BWR Mk I hardened vent valves and evaluate the accessibility for 

operation of these valves in accordance with existing design commitments assuming no 

AC power is available and to report the results to the NRC within 90 days of completion 

of the next refueling outage that starts after 1 January 2012. 

If improvements to assure accessibility are determined to be necessary they would be 

implemented consistent with operational schedules and as a separate activity. 

NRC Near-Term Task Force Recommendation 7

NRC Task Force Recommendation

The Task Force recommends enhancing spent fuel pool makeup capability and instrumentation 

for the spent fuel pool.

The Task Force recommends that the Commission direct the staff to do the following:

7.1 Order licensees to provide sufficient safety-related instrumentation, able to 

withstand design-basis natural phenomena, to monitor key spent fuel pool parameters 

(i.e., water level, temperature, and area radiation levels) from the control room.

7.2 Order licensees to provide safety-related ac electrical power for the spent fuel pool 

makeup system. 

7.3 Order licensees to revise their technical specifications to address requirements to 

have one train of onsite emergency electrical power operable for spent fuel pool makeup 

and spent fuel pool instrumentation when there is irradiated fuel in the spent fuel pool, 

regardless of the operational mode of the reactor.

7.4 Order licensees to have an installed seismically qualified means to spray water into 

the spent fuel pools, including an easily accessible connection to supply the water (e.g., 

using a portable pump or pumper truck) at grade outside the building.

7.5 Initiate rulemaking or licensing activities or both to require the actions related to the 

spent fuel pool described in detailed recommendations 7.1–7.4.”

NEI Comments and Input

The events surrounding the Fukushima Dai-ichi spent fuel pools are a good example of where 

facts discovered later have invalidated earlier conclusions. There was early speculation that 

there had been a spent fuel pool accident. Now, with the benefit of visual inspections and 
Attachment

9

samples from the four affected spent fuel pools, it is evident that the spent fuel rods did not 

experience significant failure.

The accidents at Fukushima demonstrated that spent fuel pools are robust, with a thermal 

inertia that provides time to plan and execute appropriate mitigation measures, allowing the 

early operator focus to be on stabilizing the reactor and achieving a safe reactor condition. Even 

so, the industry is taking proactive actions that include assuring that operators and the site 

emergency response team are aware of the estimated time for the spent fuel pools to reach 

200F, following a loss of spent fuel pool cooling with a starting temperature that is normally 

around 90F.

The industry recognizes that there is a benefit to remote monitoring of the spent fuel pool 

during the accident conditions to assure that operator attention and plant resources are not 

diverted from higher priority and more safety-significant activities. The industry agrees that 

there should be a process for remotely monitoring the temperature and water level in the spent 

fuel pools. The power supplies for the monitoring equipment do not need to be safety related 

based on the thermal inertia and the time taken to reach a point of extensive evaporation. 

We note that the events at Fukushima would not have benefited from safety-related power 

supplies. Safety-related requirements would not have changed the situation. We believe that 

diversity would appear to be a more important attribute. The proposal for a hardened 

seismically-qualified fuel pool spray line capable of being supplied from portable pumps outside 

of the reactor or fuel pool building would add diversity to spent fuel pool cooling capability.

Such a requirement would support the use of non-safety-related power supplies for fuel pool 

cooling and instrumentation considering the slow evolution of a spent fuel cooling event.

There are numerous spent fuel pool configurations. As a result, we believe that the commission 

should allow for a flexible, performance-based approach for spent fuel pool monitoring. The 

requirements should define what is to be achieved, leaving the industry to define in general 

guidance the implementation options based on plant configuration and needs.

The low probability of a fuel pool severe accident and the slow progression of an event that 

would lead to a severe spent fuel pool accident do not warrant the imposition of an order.

There is significant time to adjust, plan and implement mitigation measures based on the 

events at Fukushima and recent and unusual loss of spent fuel pool cooling events in U.S. 

plants.

Industry Near-Term Recommendations

Issue a Generic Letter Identify and evaluate the instrumentation and equipment needed to 

monitor spent fuel level and temperature throughout an extended loss of AC power event that 

includes depletion of DC battery power.

Attain a common understanding with the NRC staff on the methodologies and guidelines for 
Attachment

10

performing the monitoring evaluation. Inform the NRC staff of: 

(1) The methods and equipment that are used to monitor the condition of the spent fuel pools 

during an extended loss of AC power, and, if necessary, 

(2) The action plan for assuring operators have the capability for monitoring the spent fuel pool 

during an extended loss of AC power event.

(3) Report the results of the evaluations and the action plan to the NRC within 180 days of 

reaching a common understanding on the methodologies and guideline for implementing the 

generic letter.

NRC Near-Term Task Force Recommendation 8

NRC Task Force Recommendation

The Task Force recommends strengthening and integrating onsite emergency response 

capabilities such as EOPs, SAMGs, and EDMGs.

The Task Force recommends that the Commission direct the staff to further enhance the 

current capabilities for onsite emergency actions in the following ways:

8.1 Order licensees to modify the EOP technical guidelines (required by Supplement 1, 

“Requirements for Emergency Response Capability,” to NUREG-0737, issued January 1983 

(GL 82-33), to (1) include EOPs, SAMGs, and EDMGs in an integrated manner, (2) specify 

clear command and control strategies for their implementation, and (3) stipulate appropriate 

qualification and training for those who make decisions during emergencies.

8.2 Modify Section 5.0, “Administrative Controls,” of the Standard Technical Specifications for 

each operating reactor design to reference the approved EOP technical guidelines for that 

plant design.

8.3 Order licensees to modify each plant’s technical specifications to conform to the above 

changes.

8.4 Initiate rulemaking to require more realistic, hands-on training and exercises on SAMGs 

and EDMGs for all staff expected to implement the strategies and those licensee staff 

expected to make decisions during emergencies, including emergency coordinators and 

emergency directors.”

NEI Comments and Input

We agree that enhancements can be made to the process of migrating from EOPs to SAMGs 

and EDMGs to incorporate lessons learned from Fukushima. The integration of the EDMGs and 

SAMGs will be a complex and large endeavor. Such an activity needs to be split into 

manageable sections to ensure a coordinated, efficient and effective implementation. The 

industry has already started work on this activity and enhancements are being pursued.
Attachment

11

Near-term actions should focus on improving the training and implementation of EDMGs, 

SAMGs and §50.54(hh)(2) mitigation procedures and measures. Training programs should be 

reviewed and, if necessary, enhanced to assure that operators and the emergency response 

organizations are capable of making correct decisions and implementing procedures. In the 

development and implementation of these enhanced training programs, it is critical for 

operators to be more knowledgeable of mitigation measures for more likely events (abnormal 

and EOP type events) than the mitigation of extremely low probability events such as an 

extreme beyond design basis seismic event that would result in a severe accident. We suggest 

that for SAMGs, EDMGs and B5b events, the training standard should be one of familiarization.

It is important that the industry and the NRC reach a common understanding on the standards 

and scope of training with an emphasis on emergency response organizations, while assuring 

that the training focus for operators remains on the more probable events and operations. As

with other industry training programs, the National Academy for Nuclear Training in Atlanta 

would provide oversight of the training programs referenced in this section.

There needs to be further regulatory discussions on the implications of requiring Technical 

Specifications on the SAMG and EDMG training and what it means for operator exams.

New Plants

ITAAC should not be the regulatory vehicle for adjusting the licensing basis. The Part 52 change 

processes and other regulatory vehicles exist and should be used for ensuring that new plant 

licensees comply with of EOP/SAMG/EDMG implementation or other new requirements. These 

matters may be addressed after design certifications or as COLs are issued. 

Industry Near-Term Recommendations

Enhance implementation of EOPs, SAMGs and B5b strategies.

Issue a Bulletin to review and, if necessary, enhance training programs to assure that plant 

personnel are able to transition from EOPs to SAMGs and implement SAMG strategies.

Personnel should be aware of the intent and scope of SAMG and B5b strategies so that they can 

be implemented in accordance with the stations emergency preparedness activities. The level 

and depth of knowledge should be commensurate with the safety significance and probability of 

the events. 

NRC Near-Term Task Force Recommendation 9

NRC Task Force Recommendation

The Task Force recommends that the NRC require that facility emergency plans address 

prolonged SBO and multiunit events.
Attachment

12

9.1 Initiate rulemaking to require EP enhancements for multiunit events in the following 

areas: 

 Personnel and staffing,

 Dose assessment capability,

 Training and exercises, 

 Equipment and facilities

9.2 Initiate rulemaking to require EP enhancements for prolonged SBO in the following 

areas: 

 Communications capability,

 ERDS capability,

 Training and exercises,

 Equipment and facilities

9.3 Order licensees to do the following until rulemaking is complete:

 Determine and implement the required staff to fill all necessary positions for 

responding to a multiunit event. 

 Add guidance to the emergency plan that documents how to perform a multiunit 

dose assessment (including releases from spent fuel pools) using the licensee’s 

site-specific dose assessment software and approach.

 Conduct periodic training and exercises for multiunit and prolonged SBO 

scenarios. Practice (simulate) the identification and acquisition of offsite 

resources, to the extent possible.

 Ensure that EP equipment and facilities are sufficient for dealing with multiunit 

and prolonged SBO scenarios. 

 Provide a means to power communications equipment needed to communicate 

onsite (e.g., radios for response teams and between facilities) and offsite (e.g., 

cellular telephones, satellite telephones) during a prolonged SBO.

 Maintain ERDS capability throughout the accident. 

9.4 Order licensees to complete the ERDS modernization initiative by June 2012 to ensure 

multiunit site monitoring capability”

NEI Comments and Input

From discussions with some Japanese utilities, it is clear that U.S. industry emergency 

preparedness and the government (state, local and federal) emergency response infrastructure 

is more mature and is better positioned to manage an emergency on the scale of the 

Fukushima natural disasters and a nuclear emergency. U.S. company and government 
Attachment

13

organizational structures, training, drills and the strong working relationships between the 

plants and state and local response centers are significant differences.

Nevertheless, the industry acknowledges that there are lessons to be learned and 

enhancements that can be made to the industry’s emergency preparedness activities. PreFukushima enhancements to EP programs have already been identified and are about to be 

implemented via the imminent NRC EP rulemaking and the completion of the revision to 

Radiological Emergency Preparedness Manual, soon to be issued by FEMA. 

As the rule changes are being implemented, and as we learn more about the ongoing events at 

Fukushima, the NRC and industry can identify the prioritization and performance criteria for

further enhancements, as recommended in the NRC task force report.

The revised rule that is about to become effective requires a comprehensive analysis of on-shift 

staffing to validate that the emergency plan can be implemented for five categories of 

scenarios. For multi-unit event Emergency Response Organization (ERO) staffing, new criteria 

need to be defined. This includes defining the events’ characteristics, simultaneous occurrences, 

response time requirements and coping strategies. The new criteria would be appended to the 

staffing methodology prescribed in NEI 10-05. Analysis would follow the implementation of the 

initial staffing analysis requirement.

In order for the industry to implement the multi-unit staffing analysis concurrent with existing 

EP rule change, the implementation period for this rule change should be extended by one year 

in order to accommodate the development of new staffing criteria.

In the interim, as recommended in the NRC task force report, licensees could take voluntary 

action to develop a viable notification and transportation strategy to ensure staff needed to 

augment the site response would be available. 

Revised guidance can be developed and implemented within the existing rule structure to 

encompass three of the recommendations:

 Multiple release point and spent fuel pool dose assessment

 Onsite protective equipment

 Backup ERO communication

The balance of the NRC task force recommendations warrant rulemaking. Based on industryNRC staff interactions, consideration should be given to a parallel implementation-rulemaking 

approach. Such an approach would cover:

 Requiring licensed operators in the ERO outside the control room

 Drills and exercise changes

 Emergency facilities for multi-unit events (changing design basis and accident analysis 

requirements)
Attachment

14

Rulemaking in these areas would provide the necessary regulatory predictability and the basis 

for consistent implementation and inspection.

New Plants

Part 52 change processes and other regulatory vehicles exist and should be used for ensuring

that new plant licensees comply with of spent fuel cooling or other new requirements. These 

matters may be addressed after design certifications or COLs are issued, and ITAAC should not 

be the regulatory vehicle for adjusting the licensing basis.

Industry Near-Term Recommendations 

(1) Implement the revised EP rule that is about to become effective. 

(2) Engage NRC staff and other stakeholders in developing guidance for EP 

recommendations that do not require rulemaking. 

(3) For those recommendations that do require an additional rulemaking, guidance can be 

developed in parallel with the rulemaking and implementation could commence once the 

content of the final rule is known. (This is a long-term activity)

An action plan will be developed for implementation of the Fukushima-related recommendations 

beginning in 2012. 
7 September, 2011 

MEMORANDUM to: 

NRC ADVISORY COMMITTEE ON REACTOR SAFEGUARDS 

PUBLIC MEETING SEPT. 8-10,2011 ROCKVILLE, MD. 

ROOM T2-B1 TWO WHITE FLINT NORTH BUILDING 

NRC HEADQUARTERS, 11545 ROCKVILLE PIKE 

ROCKVILLE, MARYLAND 

SIRS: 

I ask that the following statements be entered in the record of this public meeting. 

1] THE CATASTROPHIC EVENTS AT FUKUSHIMA DAI-ICHI SITE IN JAPAN 

HAVE RESULTED IN A GLOBAL RADIOLOGICAL CRISIS. THE NRC HAS 

ISSUED NO WARNING TO THE PUBLIC ON THIS MOST SERIOUS HAZARD. 

2] MORE THAN 4000 TONS OF REACTOR FUEL AND SPENT FUEL POOLS ARE 

EXPOSED FOR GLOBAL DISPERSION, AIRBORNE AND SEABORNE. 

3] THESE RADIOACTIVE GASSES ARE ADDED TO THE DAILY DISCHARGE OF 

OPERATING GASSES FROM HU1\TDREDS OF REACTORS WORLD-WIDE. 

4] I ASK THAT PLUME PATHS OF DAILY REACTOR DISCHARGES BE MADE 

PUBLIC PRIOR TO ISSUING ANY FURTHER LICENSE EXTENSIONS. 

5] COMPUTER PREDICTION OF PLUME PATHS, VOLUME AND TIME OF 

DISCHARGE IS LESS ACCEPTABLE THAN ACTUAL PHYSICAL TRACKING OF 

PLUMES TO DEPOSITION SITES. 

ACCORDING TO NRC DISCHARGE RECORDS EACH 500 MEGAWATT 

REACTOR DISCHARGES SOME 20,000 CURIES PER YEAR. THE CUMULATIVE 

EXTENDED LIFE OF THESE PERMANENT TOXINS POSES AN 

UNACCEPTABLE RISK TO THE PUBLIC. 

YOUR MANDATE IS SAFETY. PLEASE ACT ON THAT RESPONSIBILITY. 

Patricia Pierce 

Site Analyst Conservation Advocate 

Millbrook Park, Rockport, Mass 01966 

?a-~l-~ ?v.-rieJ-­
MEMORANDUM 

September 7, 2011 

The White House 

Washington, D.C. 

I am responding to your form letter of August 30, 2011 on issues related to nuclear arms 

control and nuclear energy. 

My letter cited the global radiological crisis created by the Fukushima Dai-'ichi reactor 

disaster which should alter your pre-conceived plans to encourage the "peaceful use of 

nuclear energy". 

There is no safe nuclear fission. There is no way to dispose of reactor operating gasses 

other than to discharge them to the air and water. This is an unacceptable hazard. 

Reactors do not emit carbon. Cars and furnaces emit carbon monoxide. Reactors emit 

gasses that remain radioactive for thousands of years. There is no place to store reactor 

waste or to store the daily operating gasses. All operating gasses are discharged into the 

atmosphere. Each reactor discharges 20,000 to 40,000 curies per year. 

Each curie contains 37 billion emissions per second per gram. 

I repeat. All reactor operating gasses are discharged into the air and water. 

All reactor gasses are permanently toxic and cumulative. Add these toxic radioactive 

gasses to carbon monoxide plus hundreds of other pollutants, all within a few miles ofthe 

earth's surface and it is clear that life will suffocate. 

Patricia Pierce 

18 Millbrook park 

Rockport,MAO 1966 

?~Nl-L~~ ~U2-1La
essex soano o~ selectmen
 

TOWN HALL MARTIN STREET ESSEX. MASSACHUSETTS 01929 

July 11, 1989 

Advisory Committee on Reactor Safeguards 

Nuclear Regulatory Commission 

Washington, D.C. 20555 

""Sirs: 

"It is our understanding that you have statutory authority 

to ii14f.:'j':·:ene as a party in reactor licensing hearings to raise 

;any sa~~ty related issues. We ask that you intervene in the 

Seabrd'ok Reactor proceedings to require resolution of the fol­

-lowing hazardous reactor operating procedures which, if allowed, 

will cause predictable and perman ent damage to the Town of 

Essex. 

The Essex River Estuary is one of seven marine estuaries 

which form a series of interconnected pristine tidal marshes, 

coastal islands and barrier beaches extending continuously 

from Seabrook, NH, to Gloucester, MA, fourteen miles south. 

Contamination of any portion of these marshes will spread by 

tidal aetion to all portions. 

Operating discharges to air and ocean from the Seabrook 

Reactor, which is sited within the northerly portion of these 

marshes, will accumulate in these marshes causing long-lived 

isotopes to enter nut~ient cycles. These unstable radioactive 

particles being irtgested or inhaled alter cell tissue and 

genetic coding in plants, humans, animals and marine microorganisms causing genetic deformation, cancer and other disability. 

The Town of Essex will suffer irreparaale injury by reason 

of permanent contamination caused by the following unresolved 

reactor s~fety issues: 

1) Venting of fission gases to the a tmosphere in theform of "planned operating emissions" will release 

partially decayed gases, iodines and other unstable 

particles which will cool and fall over coastal 

temperature interfaces within the first hour after 

-1­
discharge leaving permanent toxic residues on coastal 

marshes and meadows. Deposition of long-lived particles 

airborne with the gases will typically occur in corridors 

where wind velocity decreases due to topography, i.e., 

behind barrier beaches, coastal uplands and islands. The 

Essex marshes twelve miles south lie precisely in the first 

hour deposition path. 

2)	 Containment of fission gases produced during radiological 

emergency is only temporary. All gases produced will be 

vented after the emergency, therebeing no other means of 

disposal. Release of active fission gases during the emergency may be necessary to avoid build up of concentrations 

leading to breach of containment and breach of heat exchange 

cooling system and consequent contaminated discharge at 

ocean outlets. ". " 

3)	 There is at present no means of disposal or storage of fission 

gases other than delayed discharge to the environment. There 

exists at present no method of accelerating decay for gases 

or solid wastes produced by atomic fission. There is no 

method for atomic fissioning that does not produce gases on 

a daily basis. 

4)	 Class 9 catastrophic radiological emergency causing widespread permanent property contamination can occur at low 

or full power operation. Loss of coolant causing core fuel 

temperatures to rise from 600°F to 40000F in seconds precludes timely warning of the public. 

5) , Seabrook Reactor having 100 tons of uranium fuel will produce 

in one fuel replacement cycle, gases equal in volume to those 

produced by vaporization of 1000 Hiroshima bombs. These gases 

will be vented as "normal operating emissions" to the atmosphere. There is no possible assurance those gases will be 

fUlly decayed or clean at the time of discharge. 

6)	 Discharges to air and ocean during radiological emergencies 

will instantly violate "permissible discharge limits" required for compliance with existing NPDES permit and FES 

required by EPA laws. Those permits were issued based 

on incomplete information which omits impact of Class 9 

emergencies on environment. The NPDES permit expires in 

1990 and should not be renewed. 

7)	 In a Class 9 catastrophic radiological emergency the reactor 

core at Seabrook cannot be isolated from the marshes and 

meltdown debris moving with ground water would leach to 

marshes. The ocean discharge would also be thoroughly contaminated at the outfall. 

-2­
8) Corrosion of heat exchange pipes can be expected to 

allow exchange of radioactive materials to contaminate 

ocean coolant discharged to ocean. 

9) Each fuel cycle releases gases produced by fission of 

100 tons of uranium to the atmosphere. 

10)	 Evacuation is not safety. It is extreme hazard. 

Being forced out of one's home onto dangerous highways 

during radiological contamination and being unable to 

return home due to permanent contamination is a violation of basic constitutional rights. 

We are not required by our constitution to suffer fatal injury 

to demonstrate damaq~to life and property. Nor can any government 

agency impose upon persons circumstances requiring loss of life and 

property. 

We consider contamination of properties and threat to life 

caused by operating discharges from Seabrook reactor to be taking 

of land without due process and a violation of our constitutional 

rights. We ask your intervention on our behalf. 

Very truly yours, 

BOARD OF SELECTMEN 

TOWN OF ESS~X, MASSACHUSETTS 

cc:	 Atomic Safety & Licensing Board, Boston, MA 

Environmental Protection Agency, Boston, MA 

Governor of Massachusetts 

Attorney General of Massachusetts 

-3­
10 CFR Part 61: 

Site-Specific Analyses for Demonstra

Compliance with Subpart C Performa

Objectives

Deborah Jackson, David Esh, Andrew Car

Office of Federal and State Materials and Environmen

Management Programs

Deborah.Jackson@nrc.gov, (301) 415-7278

David.Esh@nrc.gov, (301) 415-6705

Andrew.Carrera@nrc.gov, (301) 415-1078

586th Advisory Committee on Reactor Safeguards

September 8, 2011
Why are we here

today:

• Staff following and addressing Commission di

– Proposing rulemaking limited to site-specific analyses– Identifying technical requirements of analyses– Developing guidance outlining key parameters and ass

• Approach continues to protect public health an• Approach is risk-informed, performance-based• Approach provides flexibility to licensees to 

incorporate site information
Today’s topics and 

presenters:

Topic Prese

Discussion: Guidance for ConductingSite-Specific Analyses for Part 61

David EDWME

Draft Proposed Rule: Analysis of CommentsReceived on Preliminary Rule Language

Andrew DILR
10 CFR Part 61: 

Commission Direction
Commission Directed Staff to....

• Perform rulemaking limited to adding a site-spec

analyses prior to the disposal of significant quantDU (SRM-SECY-08-0147) and blended waste (SSECY-10-0043)

• Identify technical requirements of the site-specifi

analyses

• Develop guidance that outlines the parameters a

assumptions in conducting such site-specific ana
This rulemaking...

☑ Requires site-specific analyses to demonstrate 

compliance with Subpart C performance objectiv

☑ Identifies the technical requirements of the analy

• Definitions of analyses• Period of performance• Intruder dose criterion

☑ Develops risk-informed, performance-based gui

that outlines key parameters and assumptions

 Continues to protect public health and safety wh

providing flexibility to licensees
This rulemaking does not...

☒ Update waste the classification tables at 61.55

! The Commission directed staff not to alter waste class

☒ Comprehensively revise Part 61 framework

! The Commission directed staff to propose the necessa

resources for a possible future comprehensive revisioinform the 10 CFR Part 61 waste classification framew

☒ Remove protection of inadvertent intruder perfor

objective

! Protection of the inadvertent intruder is integral to the 

waste classification framework
Proposed Amendments:

Site-Specific Analyses

• Performance assessment — demonstrate com

with protection of the general population (§ 61

• Intruder assessment — demonstrate complian

protection of inadvertent intruders (§ 61.42)

• Long-term analysis — demonstrate how the di

system limits the potential radiological impactlong-lived waste (§ 61.13 (e))

• Update analyses at facility closure — (§ 61.28 

§ 61.52)
Proposed Amendments :

Technical Requirements

• Performance assessment :

(1) Identifies the features, events, and processes (FEPs(2) Examines the effects of these FEPs on the performa

disposal system

(3) Estimates the annual total effective dose equivalent 

any member of the public considering uncertainties, all significant FEPs

(4) Two-tiered period of performance: (1) 20,000 years; 

20,000 years analysis for long-lived waste.
Proposed Amendments:Technical Requirements• Intruder assessment:

(1) Assumes that an inadvertent intruder occupies the s

institutional controls are removed and engages in acmight unknowingly expose the inadvertent intruder to from the waste.

(2) Examines the capabilities of intruder barriers.(3) Estimates the potential annual total effective dose eq

considering associated uncertainties.

(4) Dose criterion set for intruder (500 mrem/yr TEDE).
Period of Performance:

Technical Basis• Within 20,000 years

– Including climate cycling within the compliance period will encourag

long-lived waste at more stable sites.

– A value of 20,000 years better captures radionuclide transport chara

(compared to 10,000 years).

– While 20,000 years does not capture peak risk for all wastes, it cap

than shorter values. Possibly within 10x for depleted uranium.

– Diminishing returns for longer periods (affected by increasing uncer

• Post-20,000 years

– Impacts can be better placed in proper context (NRC would comple

environmental analysis of impacts for disposal licensing actions taknon-Agreement States).
10 CFR Part 61: 

Guidance for the Low-Level

Waste Rulemaking
Purpose

• Provides guidance on conducting site-specific a

to demonstrate compliance with the performancobjectives in Part 61

• Supplements existing LLW guidance • Discusses parameters and assumptions to be u

analyses in a broad sense rather than a prescripmanner

• Provides licensees flexibility to demonstrate com

and incorporate site-specific information
Outline

• Main topics:

i. Introductionii. General Technical Analysesiii. Performance Assessment Modeling Issuesiv. Intruder Assessmentv. Stability Assessmentvi. Long-term Analysesvii. Other Considerationsviii. Performance Confirmationix. Use of other NRC Guidance Documents
10 CFR Part 61: 

Guidance for the Low-Level

Waste Rulemaking

Examples
• Discusses flexibility for short-lived waste or low 

concentrations of long-lived waste.

• Primary differences are in level of detail or justifica

the calculations.

• Provides expectations for long-term analysis.

Guidance on Period of Performance
Period of Performance: 

ExampleExample 2.3: A facility is expected to receive typical low-level wagenerated by commercial entities (e.g. limited concentrations of longwaste). The waste has concentrations of long-lived radionuclides at one tenth of the values listed in Table 1 of 

§ 61.55. Additionally, the 

expected to receive waste with long-lived radionuclides that are not Table 1 of 

§ 61.55 that is less than the natural soils surrounding the 

Conclusion: A performance assessment should be completed t

demonstrate compliance with 

§ 61.41, 

§ 61.42, and 

§ 61.44. Bec

waste is dominated by short-lived activity and long-lived concentratiolimited, specialized models and associated model support for long-teprocesses (e.g., cycling of climate) are not necessary.
Guidance on Inadvertent Intruder 

Assessment Scenarios

• Evaluate reasonably-foreseeable scenario resul

greatest dose for compliance.

• Consider site information.• Flexibility to identify reasonably-foreseeable site

scenarios in the near-term.

• For longer time frames, Part 61 default scenario

speculation about human activities.
Inadvertent Intruder Assessment: 

Scenario Analysis

• Default scenarios

– Intruder-Construction/Discovery– Intruder-Drilling– Intruder-Agriculture– Intruder-Well

• Hypothetical constructs• Provide reasonable bounds • Limit speculation about human activities• May not be appropriate at all sites
Inadvertent Intruder Assessment: 

Scenario Analysis

• Site-specific scenarios:

– Physical Information

• Waste Characteristics• Facility Design• Disposal Practices• Site Conditions

– Cultural Information

• Land Use

• Consider changes over time
Conclusions

• Staff following and addressing Commission dire

– Proposing rulemaking limited to site-specific analyses.– Identifying technical requirements of analyses.– Developing guidance outlining key parameters and assu

• Approach continues to protect public health and • Approach is risk-informed, performance-based.• Approach provides flexibility to licensees to inco

site information.
10 CFR Part 61: 

Stakeholder Comments on the 

Preliminary Proposed Rule Langua
Stakeholder Involvement 

• Preliminary proposed rule language and technic

documents published for stakeholder comments www.regulations.gov web site on May 3rd.

• May 18th public meeting.• Comment period ended on June 18th.

• Some stakeholders also presented their views d

ACRS meetings on June 23rd and July 13th.
Stakeholder Comments 

• Staff reviewed the comments and grouped them i

nine issues:

– Performance assessment– Intruder assessment– Long-term analysis– Period of performance– Agreement State compatibility– Feasibility of near surface disposal– Commission direction (SRM)– Rule language– Waste stream neutral approach

• Comments were both supportive and critical.• Staff reviewed the comments and made several li

revisions to the proposed rule language.
Path Forward

• Staff requests letter from ACRS.• Staff expects to send the proposed rule package 

Commission in January 2012.
Backup Slides
Revisions Being Considered for Prop

Rule Language
Revisions Based on 

Comments• Performance Assessment Language (§ 61.13)

– (a) A performance assessment must represent features, events, an

that can influence the ability of the waste disposal facility to limit releradioactivity to the environment. The features, events, and processconsidered in the performance assessment must represent a wide rphenomena with both beneficial and potentially adverse effects on p

The performance assessment must consider the specific technical iprovided in § 61.12(a) through (i). The performance assessment muncertainties in the projected behavior of the facility disposal system disposal facility, natural system, environment). The performance asmust identify the specific characteristics of the disposal site that are demonstrate compliance with the performance objectives in Subparpart consistent with the specific technical information found in § 61.
Revisions Based on 

Comments (continued)• Intruder Assessment Language (§ 61.7(c))

– (7) An intruder assessment quantitatively estimates the radiological 

an inadvertent intruder at a disposal facility following the loss of inst

control. The results of the intruder assessment are compared with appropriate performance objective. If intruder barriers are utilized, T

assessment must identify the intruder barriers and examine the perthe barriers. The intruder assessment must also address the effectuncertainty on the performance of the barriers. The barriers must inwith the disposed waste or limit the radiological exposure of an inadintruder over the duration of the compliance period. The technical bfor the performance of the intruder barrier will determine how long pshould be credited. An intruder assessment can employ a similar mthat used for a performance assessment, but .......
Revisions Based on 

Comments (continued)• Period of Performance Language 

– § 61.41

(b) Compliance with paragraph (a) of this section must be demonsta performance assessment that evaluates estimates peak annual dthat occurs within 20,000 years following closure of the disposal fac

– § 61.42

(b) Compliance with paragraph (a) of this section must be demonstran intruder assessment that evaluates estimates peak annual dose occurs within 20,000 years following closure of the disposal facility.
Revisions Based on 

Comments (continued)• Waste Stability Language (§ 61.7(c))

– (2) A cornerstone of the system is stability—stability of the waste an

disposal site— which minimizes the access of water to waste that h

emplaced and covered. Limiting the access of water to the waste mmigration of radionuclides, which avoids the need for long-term activmaintenance and reduces the potential for inadvertent intruders to b

the waste release of radioactivity into the environment. While stabidesirable; it isn’t necessary from a health and safety standpoint for level waste because the waste doesn’t contain sufficient radionuclidconcern. This low-activity waste (e.g., ordinary trash-type waste) teunstable, which can become a problem if it is mixed with higher actlower activity waste is mixed with the higher activity waste or long-liactivity waste, the deterioration of the unstable waste .....
Revisions Based on 

Comments (continued)• Ambiguous Language 

– § 61.7(a)

(1) Part 61 is intended to apply to land disposal of radioactive wastother methods such as sea or extraterrestrial disposal....... Technirequirements for alternative methods may be added in the future. Wmay not yet be detailed technical criteria established for all kinds odisposal that might be proposed, aAlternative methods of disposal approved on a case-by-case basis as needed. 

– § 61.55(a)

(6) Classification of wastes with radionuclides other than those listeand 2 of this section. If radioactive waste does not contain any nuc

either Table 1 or 2 of this section, it is Class A. Any waste classified 

subparagraph must be analyzed in the intruder assessment requireby § 61.42. 
Presentation to the ACR

Full Committee

AP1000 DCD Revision 19

Containment Accident Pressure

Confirmatory Analysis

September 8, 2011
Containment Accident Press

Confirmatory Analysis

• Staff performed confirmatory analysis

– Documented in SAND2009-2858

• In parallel with audit of applicants WGOT

analysis, staff performed confirmatory stuwith MELCOR

– DCD Rev. 19 revised mass and energy relea– Additional heat conductors (surrogate for gra

• Performed a number of parametric studie

the updated MELCOR model.

September 7, 2011 
Case description Pmax @ time

[psig] [s]

RES original model 55.3 @ 1500 Rev. 19 M&E rate 57.4 @ 1050 Rev. 19 M&E rate + additional heat conductors

56.8 @ 1050 

Westinghouse licensing (GOTHIC) 58.3 @ ? 

AP1000 Containment Studies (co

Major results:

September 7, 2011
Elv. of 

(2

AP1000 Containment

September 7, 2011 
orig - 457.5 kPa (51.9 psig) @ 1475 s

orig-def - 480.2 kPa (55.2 psig) @ 1475 sdef-ME19 - 495.3 kPa (57.4 psig) @ 1050 sPdesign - 59 psig 

AP1000 Containment

September 7, 2011
def-me19 - 495.3 kPa (57.4 psig) @ 1050 s

me19-HSin3 - 494.3 kPa (57.2 psig)Me19-HSin4 - 491.6 kPa (56.8 psig)Pdesign - 59 psig 

AP1000 Containment

September 7, 2011
Presentation to the ACR

Full Committee

AP1000 Structural Issues

September 7, 2011
Shield Building Thermal Anal

• WEC commitment to combine thermal and seismic dema

Rev 18 was not carried out in some cases.

• WEC performed thermal stress analysis of shield building 

thermal design demands (for combination with seismic de

– Thermal and seismic demands combined– Demand increased slightly, but remained within desig

(i.e., no design changes resulted)

• Staff reviewed analysis method and audited supporting c• Staff found WEC analysis method acceptable

– Consistent with analysis performed for thermal accid

case 

– Approach consistent with ACI-349 which permits stiffn

reduction to account for concrete cracking

September 7, 2011 
PCS Tank Seismic Analys

• WEC performed revised seismic analysis of the 

tank to be consistent with SB report commitmen

• Staff performed review and audit of supporting 

calculations

• Found analysis to be acceptable

– Method consistent with SB report commitmen– Seismic analysis performed in accordance w

3.7

– Updated analysis parameter based on realist

tank seismic demands

September 7, 2011 
1

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

AP1000® Design Control Document –

Containment Pressure Analysis

Presentation to the ACRS

by Westinghouse Electric Company, LLC

September 8, 2011
2

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Containment Peak Pressure Analysis 

Overview

• Peak pressure of 57.8 psig reported in DCD Revision 18

• Increased the steady state PCS water coverage time 

delay input value to resolve an ACRS review comment

– Containment peak pressure calculated to be 58.1 psig

• Additional input changes to the LOCA M&E model and 

containment model input were made to address other 

items that could affect the peak containment pressure 

reported in the Technical Specifications.

• Peak pressure of 58.3 psig reported in DCD Revision 19
3

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Containment Peak Pressure Analysis 

Overview

• Components of containment peak pressure calculation

– M&E release methodology

– M&E model inputs

– Containment response methodology

– Containment response model inputs

• The approved methodology that is applied in the M&E 

and containment response evaluation models is 

conservative

• Changes were made to the evaluation model inputs

– Corrections applied in the conservative direction

– Changes to reflect updated plant design information
4

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Containment Peak Pressure 

Analysis Overview

• Existing heat sinks in containment model were credited in 

order to

– Offset model input changes impact on peak containment pressure

– Maintain roughly same amount of margin reported in DCD Rev. 18

• Analysis performed in accordance with approved 

methodology

• New DCD Table 6.2.1.1-10 generated to capture key 

parameters (surface area, volume, material) of new heat 

sinks as Tier 2* information 
5

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Summary of Containment Pressure Analysis 

Results
6

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Solar Radiation Impact on LST Data

• ACRS requested further review concerning impact of solar 

radiation heating on the large-scale passive containment 

cooling test results and application to the containment 

evaluation model

• LST data were used along with data from other tests to 

validate the convective heat transfer and the condensation 

heat and mass transfer correlations

– Solar radiation had no impact on the LST data that were used for 

validation of the condensation heat and mass transfer correlation

– Solar radiation did have some impact on the LST data that were 

used for validation of the convection heat transfer correlation, but the 

heat flux data were adjusted to account for this impact
7

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Conclusions

• Model input changes were made to address items 

affecting the peak containment pressure reported in the 

Technical Specifications

• No changes were made to the plant design 

• Peak containment pressure remains under 59 psig

• NRC has reviewed the modeling changes, requested 

additional information and found the changes and 

responses to be acceptable

• Solar radiation – no impact on validation of the 

condensation correlations; the impact on validation of 

the convection correlation was addressed in the data 

evaluation
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

AP1000

® Design Control Docume

Containment Pressure Analys

Presentation to the ACRS

by Westinghouse Electric Company, LLC

September 8, 2011
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Containment Peak Pressure Analysis Overview• Peak pressure of 57.8 psig reported in DCD Revis• Increased the steady state PCS water coverage ti

delay input value to resolve an ACRS review com

– Containment peak pressure calculated to be 58.1 psig

• Additional input changes to the LOCA M&E mode

containment model input were made to address oitems that could affect the peak containment presreported in the Technical Specifications.

• Peak pressure of 58.3 psig reported in DCD Revis
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Containment Peak Pressure Analysis Overview• Components of containment peak pressure calcul

– M&E release methodology– M&E model inputs– Containment response methodology– Containment response model inputs

• The approved methodology that is applied in the M

and containment response evaluation models is conservative

• Changes were made to the evaluation model inpu

– Corrections applied in the conservative direction– Changes to reflect updated plant design information
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Containment Peak Pressure Analysis Overview• Existing heat sinks in containment model were cre

order to

– Offset model input changes impact on peak containmen– Maintain roughly same amount of margin reported in DC

• Analysis performed in accordance with approved 

methodology

• New DCD Table 6.2.1.1-10 generated to capture 

parameters (surface area, volume, material) of nesinks as Tier 2* information 
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Summary of Containment Pressure AnResults
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Solar Radiation Impact on LST Data• ACRS requested further review concerning impac

radiation heating on the large-scale passive contacooling test results and application to the containmevaluation model

• LST data were used along with data from other te

validate the convective heat transfer and the condheat and mass transfer correlations

– Solar radiation had no impact on the LST data that were 

validation of the condensation heat and mass transfer co

– Solar radiation did have some impact on the LST data th

used for validation of the convection heat transfer correla

heat flux data were adjusted to account for this impact
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Conclusions• Model input changes were made to address items 

affecting the peak containment pressure reported Technical Specifications

• No changes were made to the plant design • Peak containment pressure remains under 59 psi• NRC has reviewed the modeling changes, reques

additional information and found the changes and responses to be acceptable

• Solar radiation – no impact on validation of the 

condensation correlations; the impact on validatiothe convection correlation was addressed in the devaluation
1

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Summary of Structural Analysis 

Changes

Presentation to the ACRS

by Westinghouse Electric Company LLC

September 8, 2011
2

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Topics

Seismic and Thermal Load Combination

 Welding Requirements

 Effect of Solar Gain

PCS Tank Analysis Presented in DCD
3

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Normal Thermal Plus Seismic

Load Combination

 The Shield Building design was performed using an 

established practice for considering structural behavior 

under normal thermal loading 

- The structural design calculations had not explicitly included a 

calculated normal thermal load contribution in combination with SSE 

when the thermal effects were considered small or self relieving

 NRC Staff requested Westinghouse to demonstrate with the 

direct combination of SSE + normal thermal that the design 

was acceptable
4

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Normal Thermal Plus Seismic

Load Combination

 To validate the existing Shield Building design, 

Westinghouse updated calculations to explicitly combine 

normal thermal plus seismic

 The updated design calculations follow the ACI-349 code as 

well as the recommendations of ACI 349.1R-07, Reinforced 

Concrete Design for Thermal Effects on Nuclear Power 

Plant Structures

 The revised calculations demonstrate that no change in the 

structural design is required 

 DCD text changes were included in Revision 19 to clarify 

the licensing basis and support completion of the FSER
5

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Shield Building Weld Requirements

 Weld detailing requirements for SC structures follow the requirements of AISC 

N690

 Specified in the APP-GW-GLR-602 and DCD Rev. 19. 

 Design details (steel-to-steel and steel-to-concrete) will follow AISC N690 or 

ACI 349 codes, as appropriate, per DCD Rev. 19 commitments. The 

implementations of these commitments are included in the detailed design of 

the Westinghouse critical sections.

 APP-GW-GLR-602, Rev. 1 specifies:

 The welds that anchor the faceplates to the RC/SC connection are complete joint 

penetration (CJP) welds, as defined by AWS A3.0M/A3.0:2010. The welds that 

connect the faceplate to faceplate are also CJP welds. 

 From DCD Rev. 19, Section 3H2.2: 

 The overall configuration of the shield building is established from functional 

requirements related to radiation shielding, missile barrier, passive containment 

cooling, tornado and seismic event protection. These functional requirements led to 

establishing the design based on two primary design codes used for nuclear plant 

structures: 1) ACI 349 for reinforced concrete design, and 2) ANSI/AISC N690 for 

structural steel design.
6

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Impact of Solar Heating on 

Thermal Loading 

• Thermal loads have been evaluated conservatively for the 

Shield Building

● Thermal load case only – factor of 20% increase included

● Seismic + Thermal Cases

● Winter ΔT: 110F (70oF to -40oF)

● Summer ΔT: 45F (70oF to 115oF)

● The effects of solar gain raises the outside surface temperature 

to 129oF when the ambient temperature is 115oF. ΔT for summer 

condition still bounded by winter condition

● For winter condition, the ΔT would be reduced if solar gain is 

considered 

● The effects of solar gain for the summer case shows no significant 

effects for the load combination of ambient thermal plus SSE
7

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

PCS Tank Background 

•As part of the resolution of the SSE plus normal 

thermal issue, WEC identified that the DCD Rev 18 

was not updated to conform with a Shield Building 

Action Item

•The Action Item specified the application of 

hydrodynamic loads in the design of PCS tank

•Westinghouse has updated the calculations and 

the results are included in DCD Rev 19 
8

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

PCS Tank Design DCD Rev 15

Hard Rock Design Certification

• Equivalent static analysis applying 

maximum acceleration from time history 

analyses

• Hydrodynamic load applied as pressure

• PCS exterior wall is a critical section 

with results summarized in the DCD
9

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

PCS Tank Design DCD Rev 16-18

Extension to Soil Sites

• Westinghouse adopted Response 

Spectrum analysis method using NI05 

model for entire Nuclear Island 

Design

– Including PCS Tank

• Equivalent static analysis was applied 

using detailed model applying 

maximum acceleration from time 

history analyses for selected portions 

of shield building roof design

– Air Inlet & tension ring
10

Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Company LLC. All Rights Reserved.

PCS Tank Design Analysis

Action Item from NRC Shield Building Review (included in Shield Building 

Report)

• Required Westinghouse to apply equivalent static analysis to the PCS tank 

applying maximum acceleration from time history analyses

• A quadrant FE model of SB roof including the PCS tank, tension ring, and air 

inlet is used for the equivalent static analysis 

• Design is performed using an equivalent static methodology similar to what was 

certified in DCD Rev. 15 and similar to method used for the air inlet structure 

and the tension ring

• Hydrodynamic loads are applied as pressure and validated against a time 

history analysis 

• PCS tank design is described in DCD Section 3.7, 3.8. Appendices 3G and 3H

• The design of the reinforcement for the PCS tank critical sections is not 

changed in DCD Revision 19 
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Summary of Structural Analy

Changes

Presentation to the ACRS

by Westinghouse Electric Company LLC

September 8, 2011
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

TopicsSeismic and Thermal Load Combination

 Welding Requirements Effect of Solar Gain

PCS Tank Analysis Presented in DCD
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Normal Thermal Plus SeismicLoad Combination The Shield Building design was performed using a

established practice for considering structural behunder normal thermal loading 

- The structural design calculations had not explicitly inclu

calculated normal thermal load contribution in combinatiwhen the thermal effects were considered small or self r

 NRC Staff requested Westinghouse to demonstra

direct combination of SSE + normal thermal that twas acceptable
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Normal Thermal Plus SeismicLoad Combination To validate the existing Shield Building design, 

Westinghouse updated calculations to explicitly conormal thermal plus seismic

 The updated design calculations follow the ACI-34

well as the recommendations of ACI 349.1R-07, RConcrete Design for Thermal Effects on Nuclear PPlant Structures

 The revised calculations demonstrate that no cha

structural design is required 

 DCD text changes were included in Revision 19 to 

the licensing basis and support completion of the 
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Shield Building Weld Requirements Weld detailing requirements for SC structures follow the requireme

N690

 Specified in the APP-GW-GLR-602 and DCD Rev. 19. 

 Design details (steel-to-steel and steel-to-concrete) will follow AISC 

ACI 349 codes, as appropriate, per DCD Rev. 19 commitments. Timplementations of these commitments are included in the detailed the Westinghouse critical sections.

 APP-GW-GLR-602, Rev. 1 specifies:

 The welds that anchor the faceplates to the RC/SC connection are com

penetration (CJP) welds, as defined by AWS A3.0M/A3.0:2010. The wconnect the faceplate to faceplate are also CJP welds. 

 From DCD Rev. 19, Section 3H2.2: 

 The overall configuration of the shield building is established from func

requirements related to radiation shielding, missile barrier, passive concooling, tornado and seismic event protection. These functional requiestablishing the design based on two primary design codes used for nstructures: 1) ACI 349 for reinforced concrete design, and 2) ANSI/AISstructural steel design.
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Impact of Solar Heating on Thermal Loading • Thermal loads have been evaluated conservativ

Shield Building● Thermal load case only – factor of 20% increase inclu● Seismic + Thermal Cases

● Winter 

ΔT: 110F (70

oF to -40

oF)

● Summer 

ΔT: 45F (70

oF to 115

oF)

● The effects of solar gain raises the outside surface 

to 129

oF when the ambient temperature is 115

oF. 

Δ

condition still bounded by winter condition

● For winter condition, the 

ΔT would be reduced if so

considered 

● The effects of solar gain for the summer case shows n

effects for the load combination of ambient thermal plu
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

PCS Tank Background 

•As part of the resolution of the SSE plus no

thermal issue, WEC identified that the DCD was not updated to conform with a Shield BAction Item

•The Action Item specified the application o

hydrodynamic loads in the design of PCS t

•Westinghouse has updated the calculation

the results are included in DCD Rev 19 
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

PCS Tank Design DCD Rev 15Hard Rock Design Certification• Equivalent static analysis applying 

maximum acceleration from time history analyses

• Hydrodynamic load applied as pressure• PCS exterior wall is a critical section 

with results summarized in the DCD
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

PCS Tank Design DCD Rev 16-18Extension to Soil Sites• Westinghouse adopted Response 

Spectrum analysis method using NI05 model for entire Nuclear Island Design

– Including PCS Tank

• Equivalent static analysis was applied 

using detailed model applying maximum acceleration from time history analyses for selected portions of shield building roof design

– Air Inlet & tension ring
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

PCS Tank Design AnalysisAction Item from NRC Shield Building Review (included in ShiReport)• Required Westinghouse to apply equivalent static analysis to the P

applying maximum acceleration from time history analyses

• A quadrant FE model of SB roof including the PCS tank, tension ri

inlet is used for the equivalent static analysis 

• Design is performed using an equivalent static methodology simila

certified in DCD Rev. 15 and similar to method used for the air inleand the tension ring

• Hydrodynamic loads are applied as pressure and validated agains

history analysis 

• PCS tank design is described in DCD Section 3.7, 3.8. Appendice• The design of the reinforcement for the PCS tank critical sections 

changed in DCD Revision 19 
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Questions
1

Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LLC. All Rights Reserved.

AP1000® Design Certification

Summary of DCD Revision 19 Changes

Presentation to the ACRS

September 8, 2011

Westinghouse Electric Company LLC
2

Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Agenda Topics

● Design Control Document Revision 19 summary

● Discussion Structural Analysis Changes 

– Shield building load combination

– PCS tank structural design

● Containment vessel pressure analysis
3

Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LLC. All Rights Reserved.

● DCD Rev 19 was required to capture the resolution of NRC 

staff confirmatory items

● Additional DCD text was designated with Tier 2* controls:

– Structural information including shield building details

– Structural design information was added, designated, or clarified as Tier 2*

– Containment debris limits

– The ACRS recommended that the containment debris limit be controlled

– Information in Section 6.3 related to debris was designated as Tier 2*

– Additional Tier 2* information was added in agreement with the NRC 

Staff based on regulatory requirements, guidance, and review. 

● Clarifications and consistency improvements: 

– Chapter 16 Technical Specifications

– Tier 1 editorial improvements

– Referenced document citations

DCD Revision 19: Scope of Revisions
4

Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LLC. All Rights Reserved.

DCD Revision 19: Scope of Revisions

● Conforming revisions to address confirmatory review of:

– Shield Building Load Combination

– PCS Tank Analysis Methodology

– Containment Vessel Calculated Peak Internal Pressure

– Each topic above and the changes included in DCD Rev. 19 were 

the subject of NRC public meetings

● The DCD Rev 19 “design” is the same as DCD Rev 18

● DCD R19 is ready for certification

No design changes included in DCD Revision 19
5

Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Shield Building Load Combination Topic

● The design and analysis requirements for the 

Shield Building steel concrete composite wall 

including treatment of normal thermal plus seismic 

load combination evaluation is documented in new 

DCD section 3.8.4.5.5.

● Tables in Appendix 3H are updated to include the 

ambient thermal plus seismic load combination

DCD Revision 19
6

Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Shield Building PCS Tank Topic

● The use of equivalent static analysis for the PCS 

tank is summarized in Section 3.7 

● Appendix 3G includes a more detailed description 

of the use of equivalent static analysis for the PCS 

tank

● A table (3H.5-15) and figure (3H.5-11, Sheet 6) 

added for additional design information on the PCS 

tank

DCD Revision 19
7

Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LLC. All Rights Reserved.

Containment Vessel Calculated Internal Peak 

Pressure

● New calculated peak internal pressure is 58.3psig 

(compared to 57.8 psig) 

– ACRS comment related to the water film steady state 

coverage and additional updates

● Section 6.2 was revised to address updated CV 

peak pressure

– Input changes in mass and energy model and 

containment response model

● Conforming change in Technical Specifications

DCD Revision 19
Proposed RG 1.115,

Protection Against Turbine 

Missiles

Simon C. F. Sheng Steven Jones

Division of Component Integrity Division of Safety 

(NRR)

John Honcharik

Division of Engineering (NRO)

ACRS Subcommittee Meeting

September 8, 2011 
• The ACRS Subcommittee Comments

• The GDC 4 Requirement• The Current NRC Position on Protection Ag

Turbine Missiles

• Objectives of the Proposed RG 1.115• Operating Experience since 1977• Enhancements in the Proposed RG 1.115• Industry Comments• Conclusions

Overview
The ACRS Subcommittee 

Comments

1. Clearly Define SSCs to be Protected2. Consider Non-Nuclear Power Plant Experi3. Consider Risk-Informed Approach4. Provide Turbine Missile Risk Goal for New 

Reactors

5. Clarify Use of Table 1 and Use of Barriers 

6. Clarify When Table 1 is Applicable (

√

)

7. Expand RG to Include Detailed Technical 

Guidelines 
The GDC 4 Requirement

GDC 4, “Environmental and Dynamic 

Effects Design Bases,” requires:

“These structures, systems, and 

components [SSCs important to safety] shall be appropriately protected against dynamic effects, including the effects of missiles...that may result from equipmenfailures....”
The Current NRC Position on 

Protection Against Turbine Missiles

• By Turbine Orientation

RG 1.115 (July 1977)

• By Control of Turbine Missile Generation 

Frequency

Hope Creek SER (July 1986) SRP 3.5.1.3, “Turbine Missiles” (March 

• By Missile Barriers

RG 1.115 (July 1977)
Objectives of the Proposed 

RG 1.115• Assures Turbine Failure Is a Negligible Contribu• Makes the RG Self-Contained Including All Acce

Protection Methods Against Turbine Missiles

• Clarifies SSCs to Be Protected from Turbine Mis

(ACRS Comment 1)

– Includes Safe Shutdown Functions (e.g., Makeup 

Heat Sink, and Long-Term Decay Heat Removal)

– Excludes Functions Necessary Only for Other Un

Design Basis Events (e.g., High-Head Safety InjeContainment)

• Assesses Operating Experience since 1977
Operating Experience Since 

1977

Reassess Failure Data by Reviewing

Before 1995

• NUREG-1275

After 1995

• Licensee Event Reports (LERs)• International Incident Reporting System• INPO Significant Event Notifications

Purpose: To Explore the Possibility of Revis

the Current P

1 and P

4 Criteria
Defining P1, P2, and P3

The Ultimate Concern: The Probability of F

an Essential System P4 Caused by Turbi

Missiles

P4 = P1 x P2 x P3

• P1: The Probability of Turbine Missile Ge• P2: The Probability of Ejected Missiles St

an Essential System

• P3: the Probability of the Struck Essentia

System Losing Its Safety Function
Findings on Review of Turbine 

Operating Experience 

• An Event in 1991 Gives a Point Estima

1E-3 per Turbine-year for a DestructivTurbine Overspeed Event 

• Turbine Operating Record has Improv

General During the Past 15 Years

• Still has Unignorable No. of Events 

Resulting in Scrams, Shutdowns, and Outage Delays Per Year
Conclusions Based on Review of 

Turbine Operating Experience 

• Consider Nuclear Power Plant Experience Only 

Nuclear Operating Practices, Maintenance, Testand Inspections Changed After the Salem 2 Eve(ACRS Comment 2)

• Operating Experience is Consistent with the Tur

Failure Rate of 1E-4 per Turbine-Year (RG 1.115

• Maintain the Current Criteria of P1 (Hope Creek 

and P

4 (RG 1.115) 
Application of a Risk-Informed 

Approach 

• Applications Conforming to RG 1.174 are 

Considered on a Case-By-Case Basis (A

Comment 3)

• Risk Goal is not Defined for Turbine Miss

New Reactors (ACRS Comment 4)
Enhancements in the Proposed 

RG 1.115

• Provides Guidance for High-Trajectory M• Define SSCs to be Protected (ACRS Com• Clarifies the Current NRC Emphasis on P

1986 Hope Creek SE and the 2007 SRP

• Permits the Approach of Considering P

1, 

P

3

• Validates Operating Experience (NUREG

LERs, IRS, INPO, etc.) since 1977
Provides Guidance for HighTrajectory Missiles

Different P1s for Low-trajectory and High-trajectory 

Missiles

P1 = P1f x P1p + P1o 

• P1f is probability of disk failure based on 

Probabilistic Fracture Mechanics considering 

• P1p is probability of the failed disk piece 

penetrating turbine case based on energy dissipation (different values for LTMs and HT

• P1o is probability of overspeed protection sys

failure (quickly resulting in disk failure and tucase penetration)
Clarifies the Current Emphasis 

on P

1

Favorably Oriented

• Low-trajectory: no additional analysis (

1.115)

• High-trajectory: 1E-4 (1986 Hope Cree

SER)

Unfavorably Oriented

• Low-trajectory: 1E-5 (1986 Hope Cree• High-trajectory: No Additional Analysis 

Low-Trajectory Analysis is Bounding
Turbine Orientation
Permits the Approach of 

Considering P

1, P

2, and P

3

Unfavorably Oriented/Both Trajectories

P1 (<1E-4) x P

2 x P

3 < 1E-7

Features

• Retain the RG 1.115 criterion of 1E-7 for the 

probability of failure of an essential system cby LTMs

• Relax the current P1 criterion for an unfavora

oriented turbine from 1E-5 to 1E-4 when P

2 a

are also considered
Industry Comments (Jan. 2010)

The Proposed RG Considers: • Pathways for High Trajectory Missiles• Robust Rotor Designs• New Rotor Designs within Current Regulatory P• Credit for Existing Structures as Missile Barriers• Sites with Multiple Units• Applications Conforming to RG 1.174 on a Case

Basis

• Future Conforming Changes to the SRP• Probability for Low-Trajectory Turbine Missiles

Unchanged
Industry Comments (June 2011)

Soliciting Comments Again is Required BecRG Revision (ML103350136) Incorporating Comments is Rather SignificantThe Proposed RG Considers• Comments Involving Definitions and Wor

(Majority)

• Review of Risk-Informed Approach on a C

Case basis to include Generic Application
Conclusion

The Proposed RG 1.115 

• Becomes Self-contained, Providing Preferred 

Acceptable Approaches and Acceptance CriteAgainst LTMs and HTMs

• Is Consistent with the Current Criteria Empha

• Considers the Approach Using P1, P2 , and P• Considers Risk-Informed Approach Case-by-• Has Considered 2010 and 2011 Industry Com• Has Fully Addressed 6 of 7 ACRS Comments

- Will Explore Means to Provide Detailed Tec

Guidelines as a Long-Term Goal (ACRS Comment 7)
Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LL

AP1000® Design Certification

Summary of DCD Revision 19 Changes

Presentation to the ACRS

September 8, 2011

Westinghouse Electric Company LLC
Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LL

Agenda Topics● Design Control Document Revision 19 sum● Discussion Structural Analysis Changes 

– Shield building load combination– PCS tank structural design

● Containment vessel pressure analysis
Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LL

● DCD Rev 19 was required to capture the resolutio

staff confirmatory items

● Additional DCD text was designated with Tier 2* c

– Structural information including shield building details

– Structural design information was added, designated, or clarified 

– Containment debris limits

– The ACRS recommended that the containment debris limit be co– Information in Section 6.3 related to debris was designated as T

– Additional Tier 2* information was added in agreement 

Staff based on regulatory requirements, guidance, and 

● Clarifications and consistency improvements: 

– Chapter 16 Technical Specifications– Tier 1 editorial improvements– Referenced document citations

DCD Revision 19: Scope of Revision
Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LL

DCD Revision 19: Scope of Revision● Conforming revisions to address confirmatory rev

– Shield Building Load Combination– PCS Tank Analysis Methodology– Containment Vessel Calculated Peak Internal Pressure– Each topic above and the changes included in DCD Re

the subject of NRC public meetings

● The DCD Rev 19 “design” is the same as DCD R● DCD R19 is ready for certification

No design changes included in DCD Revisio
Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LL

Shield Building Load Combination Topic● The design and analysis requirements for 

Shield Building steel concrete composite wincluding treatment of normal thermal plus load combination evaluation is documenteDCD section 3.8.4.5.5.

● Tables in Appendix 3H are updated to incl

ambient thermal plus seismic load combin

DCD Revision 19
Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LL

Shield Building PCS Tank Topic● The use of equivalent static analysis for th

tank is summarized in Section 3.7 

● Appendix 3G includes a more detailed des

of the use of equivalent static analysis for tank

● A table (3H.5-15) and figure (3H.5-11, She

added for additional design information on tank

DCD Revision 19
Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LL

Containment Vessel Calculated Internal P

Pressure

● New calculated peak internal pressure is 5

(compared to 57.8 psig) 

– ACRS comment related to the water film stead

coverage and additional updates

● Section 6.2 was revised to address update

peak pressure

– Input changes in mass and energy model and 

containment response model

● Conforming change in Technical SpecificaDCD Revision 19
Westinghouse Non-Proprietary Class 3

© 2011 Westinghouse Electric Company LL

Questions and Discussion
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

AP1000

® Design Control Docume

Containment Pressure Analys

Presentation to the ACRS

by Westinghouse Electric Company, LLC

September 8, 2011
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Containment Peak Pressure Analysis Overview• Peak pressure of 57.8 psig reported in DCD Revis• Increased the steady state PCS water coverage ti

delay input value to resolve an ACRS review com

– Containment peak pressure calculated to be 58.1 psig

• Additional input changes to the LOCA M&E mode

containment model input were made to address oitems that could affect the peak containment presreported in the Technical Specifications.

• Peak pressure of 58.3 psig reported in DCD Revis
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Containment Peak Pressure Analysis Overview• Components of containment peak pressure calcul

– M&E release methodology– M&E model inputs– Containment response methodology– Containment response model inputs

• The approved methodology that is applied in the M

and containment response evaluation models is conservative

• Changes were made to the evaluation model inpu

– Corrections applied in the conservative direction– Changes to reflect updated plant design information
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Containment Peak Pressure Analysis Overview• Existing heat sinks in containment model were cre

order to

– Offset model input changes impact on peak containmen– Maintain roughly same amount of margin reported in DC

• Analysis performed in accordance with approved 

methodology

• New DCD Table 6.2.1.1-10 generated to capture 

parameters (surface area, volume, material) of nesinks as Tier 2* information 
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Summary of Containment Pressure AnResults
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Solar Radiation Impact on LST Data• ACRS requested further review concerning impac

radiation heating on the large-scale passive contacooling test results and application to the containmevaluation model

• LST data were used along with data from other te

validate the convective heat transfer and the condheat and mass transfer correlations

– Solar radiation had no impact on the LST data that were 

validation of the condensation heat and mass transfer co

– Solar radiation did have some impact on the LST data th

used for validation of the convection heat transfer correla

heat flux data were adjusted to account for this impact
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Conclusions• Model input changes were made to address items 

affecting the peak containment pressure reported Technical Specifications

• No changes were made to the plant design • Peak containment pressure remains under 59 psi• NRC has reviewed the modeling changes, reques

additional information and found the changes and responses to be acceptable

• Solar radiation – no impact on validation of the 

condensation correlations; the impact on validatiothe convection correlation was addressed in the devaluation
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan
Westinghouse Non-Proprietary Class 3 © 2011 Westinghouse Electric Compan

Effect of Solar Radiation on Calculated Pressure• The conservative Shield Building heat-up calculat

resulted in an increase of the interior wall tempera~0.001 °F. Therefore, an insignificant amount of hbe added from the inside surface.

• Assume the average incoming air temperature inc

3.5°F (0.25*129 F+0.75*115 F) due to solar heatinoutside surface of the Shield Building.

• The increase in the calculated peak containment p

has been calculated to be 0.05 psi for a 10 F increambient air temperature

• Therefore, a conservative calculated increase in p

containment pressure would be less than 0.02 psi
1

Dept of Philosophy

135 Baker Hall

Carnegie Mellon University 

Pittsburgh PA 15213

August 12, 2011

Mr Weidong Wang, Senior Engineer

ACRS/TSB, Nuclear Regulatory Commission

Mailstop 2 E26 TWFN

Rockville, Maryland 20852 

References: 

1. Email from Billy Gleaves, Sr Project Manager dated 28 June 2011, "RE: Request to listen via teleconference 

[PUBLIC MEETING WITH WESTINGHOUSE ELECTRIC COMPANY ON THE AP1000

DESIGN CERTIFICATION - SHIELD BUILDING ROOF PASSIVE CONTAINMENT COOLING

WATER STORAGE TANK ANALYSIS Thursday, June 30, 2011 9:00 a.m. - 11:30

a.m.]"

2. "Evaluation of the Effect of the AP1000 Enhanced Shield Building Design on the Containment 

Response and Safety Analysis", APP-GW-GLR-097, Rev. 1, submitted to the NRC as part of 

docket on AP1000 rulemaking, as enclosure 4 to DCP-NRC-002998, August 6, 2010.

3. "A Review -- Cooling by Water Evaporation Over Roof" by G. N. Tiwari, A. Kumar, and M. S. 

Sodha, in Energy Conversion Management, Vol. 22, pp. 143 to 153, 1982. 

4. Letter from S G Sterrett to Billy Gleaves dated 7 July 2011 "Thermal loads and effects due to 

radiative heating and cooling of AP1000 shield building exterior surface, which are in addition to all 

thermal loads and effects due to ambient air temperature" (Written question submitted regarding 

PUBLIC MEETINGS WITH WESTINGHOUSE ELECTRIC COMPANY ON REV 19 OF THE 

AP1000 DCD that were held on June 30, 2011) 

SUBJECT: Question for ACRS Meeting on August 16th, 2011 (Rev 19 of AP1000 DCD) concerning whether 

solar radiation on the physical model was accounted for in interpretating experimental data in the "Large 

Scale Test" that was used to validate WGOTHIC, which is used in Rev 19 calculations for predicting heat and 

mass transfer aspects of the effectiveness of Passive Containment Cooling System in reducing containment 

pressure. 

1. Background to the Problem

2. Technical Discussion of the Problem 

3. Question to the ACRS about WGOTHIC validation for Rev 19 Containment Pressure Calcs

4. Concluding Remark on Significance of Question

1. Background to the Problem (from which the question about WGOTHIC validation using the

PCS (Passive Containment Cooling System) Large Scale Test (LST) arises)

In the meetings about Rev 19 of the AP1000 DCD held on June 30, 2011, the topic of including 

thermal loads on the AP1000 shield building was discussed, and various sections of revision 19 of 

the AP1000 DCD were cited, including Appendix 3H. In an earlier letter addressed to the NRC's

Billy Gleaves, (Ref. 4), which I attach to this letter for convenience, I discussed that issue as it 

related to the AP1000 nuclear safety accident analyses and analysis of the shield building 
2

structure: It is clear from looking at the values of the thermal loads listed in Appendix 3H of Rev 19 

of the AP1000 DCD that Westinghouse assumed the building exterior surface temperatures to be 

bounded by the ambient air temperatures. It is also a matter of very basic science that doing so is 

not correct. 

The quantitative values of the neglected quantities are not small (~ 30 degrees F or more 

difference added onto the high end of the range; about half that added on the low end of the 

range). The data presented by Westinghouse in Appendix 3H of Rev 19 of the AP1000 DCD

implies that Westinghouse and/or the NRC staff did not consider, and/or did not realize that it was 

relevant to take into account the fact that there can be radiative heating of an exterior surface due 

to the sun, and radiative cooling of an exterior surface due to radiation to the night sky. These 

temperature changes are distinct from, and in addition to, seasonal and daily temperature changes 

due to seasonal and daily temperature changes in the ambient air temperature. 

The fact that Westinghouse made this error (neglecting the effect on building exterior surface 

temperatures due to radiative heat gains due to the sun (solar radiation) and radiative losses to the 

night sky) in the work done for the Rev 19 changes raises the question of whether there is a more 

fundamental problem with the safety analysis of the AP1000: if they really didn't know that they 

needed to consider the effect of heat of solar radiation for the Rev 19 calculations for the shield 

building exposed to the sun, did they know to do so when interpreting the test results of the Large 

Scale Test of the Passive Containment Cooling System? The steel containment as installed is 

inside the concrete shield building and is not exposed to the sun, so there would be a problem if 

the scale model of the steel containement was exposed to the sun during the test.

In a Westinghouse document submitted as part of Rev 19, the following photograph of the Large 

Scale Test Facility is provided: 

 
3

If the above is a photograph of the site on which the test was performed (i.e., if the test was 

performed outdoors during the day), which I believe it is, then the wetted surface of the Large 

Scale Test (LST) of the Passive Containment Cooling System (PCS), was in the presence of the 

sun when the experimental test data was taken. The figure below, which is from an article in an 

engineering journal (Ref. 3 ) is applicable to that situation, and the factors depicted in it need to be 

taken into account when interpreting the test data: 

Now, compare the two situations: the PCS LST physical model in the outdoors, and the PCS 

under the conditions at which it is supposed to operate: 

Large Scale Test (LST) -- Outdoors in Presence of Sunlight 

The above figure (Figure 1 of Tiwari 1981) correctly depicts the role of the sun in the Large 

Scale Test situation of the Passive Containment Cooling System (PCS) LST, which, it 

appears, was performed outdoors, in the presence of sunlight. 

In the LST model, which is a physical model, the baffle/shield building was represented, if at 

all, using a transparent material. The physical model's being in the presence of sunlight

thus aided evaporation in the PCS LST test. 

146 TIWARI et al.: A REVIEW 

(a) 

Inlet of 

water 

] Flow direction ,,, ] 

0 ~ y l -." ........ I Outlet of 

l ; :[ V////////////////////////A x Room temperature T R 

(b) ]- L ,/ 

Inlet *~ ~~~"~~ l 

dy Fig. 1. (at Schematic sketch of, "Flowing water over the roof" system. 

water system. 

," Outlet 

(b) Overside view of the flowing 

The temperature distribution in the concrete roof is 

governed by the heat conduction equation viz. 

(~O(x, t) ~20(X, t) - ~ -- (1) ~t ~/X 2 

where 

K 

pc 

is the thermal diffusivity of the concrete material. 

Refering to Fig. lb, the energy balance equation 

for water moving over the roof along y-direction is 

aT,,, ?~Tw\ 

bdpwcw -- ?4 + ,i,,,cw ~)dy 

= [rails - Q, - Q,, - Qc + ho(0l~-o - T.,)]bdy 

where (2) 

K, 23 ho = ~' [0.14(6,P,) / + 0.664(P,)L'3(R~)'"2][19] 

O, = h,(Tw - T,) 

Qc = h~(Tw - L) 

Q,, = 0.013h¢(pw- ?pot 

h'=[ Ewa{(~'w+273)'-('~+261)'}]'w-'. 

h~ = 5.678(1 + 0.85Av) 

Av = (% - Uo). (2at 

values of the relevant parameters as discussed in 

detail in the Appendix. To proceed further, we have to 

linearize the expression for Q~ this is achieved by 

noting that the observed dependence of saturation 

vapour pressure of water (p) can be expressed by a 

linear relation in the (narrow) temperature range of 

interest viz 

p = RIT+ R 2 (3) 

where R1 and R 2 are two constants to be obtained 

from the saturation vapour pressure data [22] by 

least square curve fitting. 

Substituting the values of Q,, Qc, Q,, and p from 

equations (2a) and (3) in equation (2), one obtains 

c~T,, aT,, 

Mw ?t + fi2wCw T = bH(TI - Tw), (4) (), 

where 

1 

T 1 = ~[rlH~ + ho0]x=o + HIT, - RoR2(I - 7)] 

H = ho + h, +he+ RoR1 

HI = h, + h,. + ?RoRl 

Ro = 0.013he 

Mw = bdpwcw. 

Equation (4) is a general energy balance equation 

which can be simplified by putting 

(it rhw = 0 for open roof pond, and 
4

Conditions under which AP1000 PCS is designed to operate -- Inside shield building, largely 

shielded from Sunlight

The installed situation for which the AP1000 Passive Containment Cooling System is to 

perform its safety function of heat removal from the steel containment is inside the concrete 

shield building, and the concrete shield building is opaque to solar insolation. Whatever the 

weather outdoors, the wetted surface of the steel containment from which evaporative losses 

are taken credit for in the AP1000 safety analysis is largely shielded from receiving the 

benefit of sunlight (solar insolation) in the situation in which the PCS operates, as installed in 

an AP1000 nuclear power plant. 

Thus there might well have been more evaporation, and more heat removal, earlier, in the LST 

experimental test situation than there will be in the situation in which the PCS is actually to operate

when installed in an AP1000 nuclear power plant. At any rate, accuracy calls for considering the 

important relevant factors in a calculation, and the factor of whether or not a surface is in the 

presence of solar radiation or not is a relevant factor in the calculation of heat transfer. 

I have so far not run across any discussion of the fact that the test model of the steel containment 

shell was located in the sun whereas the actual containment is located within the shield building, 

largely shaded from sunlight. 

2. Technical Discussion of the Problem

2a. WGOTHIC Validation of Indoor Systems Using Outdoor Test 

The problem is that it appears that in the test situation (PCS LST) against which the computer code 

WGOTHIC was compared, the wetted surface was exposed to solar insolation (i.e., radiative 

heating from sunlight was present), whereas the situation WGOTHIC is being used to make 

predictions about is one in which it is not: inside the shield building, which is where the PCS 

delivers the water film over the steel containment. The interior is largely shielded from sunlight. 

The Westinghouse presentation at an NRC meeting on 30 June 2011 presented this figure:

 

 
5

It was also stated that the computer code WGOTHIC was used in the safety analysis for the 

AP1000 to predict PCS effectiveness in removing heat from the containment, and thus to predict its 

effectiveness in reducing containment pressure. Per the docket materials submitted describing 

the analysis performed in calculating containment pressure for Rev 19 changes, the computer code

was validated by comparing the results that WGOTHIC predicted for the LST test with the results 

obtained experimentally in the LST test. 

Since the LST test was conducted in the presence of sunlight, and the WGOTHIC model of the 

PCS performance was validated against it, won't the WGOTHIC model of the AP600/AP1000 

containment response tend to overestimate the evaporative losses that will occur when the PCS 

operates as installed in the AP1000 plant? I ask this because, in the AP1000 plant, as in the 

AP600 plant, the wetted containment surface is indoors, in the dark, inside the shield building. 

Since evaporative losses reduce containment pressure, doesn't this mean that, unless the effect of 

the sunlight is quantified and accounted for in some way, using this approach to validate a 

computer code such as WGOTHIC results in a computer code that underestimates the 

containment pressure ?

2b. Some Points of Basic Physics

The symbol for solar radiation in the cited paper (Tiwari 1981) is Hs , as indicated in the 

nomenclature list on the first page of the paper. Hs occurs in the general energy balance equation

for figure 1(b) in Tiwari 1981's paper (reproduced above). The general energy balance is equation 

(2) of the Tiwari 1981 paper; the energy balance is basic physics and not a matter of 

controversy or interpretation. 

 

I would like to emphasize something I said as a participant via telephone in the NRC public 

meeting that was held on the morning of June 30th, 2011: that neither the effect of radiative heat 

gains (via solar radiation) nor the effect of radiative heat losses (via radiation to the night sky) is

captured by considering the effect of ambient air temperature. 

To get this point across, I draw your attention to the portion of Tiwari's paper on cooling by water 

evaporation over roofs that makes a general comment about the cycles of solar radiation and 

cycles of temperature change due to daily night-and-day cycles. This paragraph of the paper (p. 

146) makes clear that they are two distinct factors. Hs is the symbol for solar radiation, and Ta is 

the symbol for ambient air temperature:

146 TIWARI et al.: A REVIEW 

(a) 

Inlet of 

water 

] Flow direction ,,, ] 

0 ~ y l -." ........ I Outlet of 

l ; :[ V////////////////////////A x Room temperature T R 

(b) ]- L ,/ 

Inlet *~ ~~~"~~ l 

dy Fig. 1. (at Schematic sketch of, "Flowing water over the roof" system. 

water system. 

," Outlet 

(b) Overside view of the flowing 

The temperature distribution in the concrete roof is 

governed by the heat conduction equation viz. 

(~O(x, t) ~20(X, t) - ~ -- (1) ~t ~/X 2 

where 

K 

pc 

is the thermal diffusivity of the concrete material. 

Refering to Fig. lb, the energy balance equation 

for water moving over the roof along y-direction is 

aT,,, ?~Tw\ 

bdpwcw -- ?4 + ,i,,,cw ~)dy 

= [rails - Q, - Q,, - Qc + ho(0l~-o - T.,)]bdy 

where (2) 

K, 23 ho = ~' [0.14(6,P,) / + 0.664(P,)L'3(R~)'"2][19] 

O, = h,(Tw - T,) 

Qc = h~(Tw - L) 

Q,, = 0.013h¢(pw- ?pot 

h'=[ Ewa{(~'w+273)'-('~+261)'}]'w-'. 

h~ = 5.678(1 + 0.85Av) 

Av = (% - Uo). (2at 

G,, P, and R,, are the Grashof, Prandtl and Reynolds 

numbers respectively. Equation (2at is derived from 

the Lewis relation by substituting the numerical 

values of the relevant parameters as discussed in 

detail in the Appendix. To proceed further, we have to 

linearize the expression for Q~ this is achieved by 

noting that the observed dependence of saturation 

vapour pressure of water (p) can be expressed by a 

linear relation in the (narrow) temperature range of 

interest viz 

p = RIT+ R 2 (3) 

where R1 and R 2 are two constants to be obtained 

from the saturation vapour pressure data [22] by 

least square curve fitting. 

Substituting the values of Q,, Qc, Q,, and p from 

equations (2a) and (3) in equation (2), one obtains 

c~T,, aT,, 

Mw ?t + fi2wCw T = bH(TI - Tw), (4) (), 

where 

1 

T 1 = ~[rlH~ + ho0]x=o + HIT, - RoR2(I - 7)] 

H = ho + h, +he+ RoR1 

HI = h, + h,. + ?RoRl 

Ro = 0.013he 

Mw = bdpwcw. 

Equation (4) is a general energy balance equation 

which can be simplified by putting 

(it rhw = 0 for open roof pond, and 

(ii) mw = 0; 

fi~,, = 0 for water film (spray/gunny bag). 
6

 

To put this in nontechnical terminology: The difference between ambient air temperature in night 

and in day is one thing (diurnal cycling, indicated by (7b)), and the difference due to the very 

presence or absence of solar insolation is another thing. The presence or absence of solar 

insolation is the difference between being in the shade and being in direct sunlight, at the same 

ambient air temperature (indicated by (7a)). 

Both diurnal thermal cycling (due to ambient air temperature daily cycles) and daily temperature 

variation due to solar insolation can be periodic for a particular engineering project, and both are in 

some manner due, ultimately, to the heat of solar radiation. They are, however, two distinct, 

quantifiable effects whose variation does not coincide in time and place, and neither includes the 

other. 

2.c. Conclusion of the above considerations: The effects of solar insolation (sunlight hitting the 

surface of something) that were present in the Large Scale Test of the Passive Containment 

Cooling System (and so aided evaporation), but which are not going to be present in the actual 

situation to which the safety analysis applies (since the wetted surface from which evaporation is 

supposed to take place is indoors, shielded from sunlight), should be quantified and subtracted 

from the LST test results before comparing it to the WGOTHIC analysis. The question is: was this 

done? Did the ACRS check whether it was done when they approved the designs based upon the 

analyses using the computer models whose validation appealed to this test? The difference 

between the test situation and the situation for which WGOTHIC is to be used for prediction needs 

to be taken into account in some manner. Otherwise, the LST does not serve to validate the 

WGOTHIC analysis for the PCS as it will perform when it is installed and used in the AP1000 plant. 

The photograph of the Small Scale Test Facility, also taken from material submitted for rev 19 of 

the AP1000 DCD, likewise portrays it outdoors, so agreement between the small scale test 

experiments run on this facility, and the large scale tests cannot be appealed to in order to dismiss 

the significance of the test being performed outdoors: 

surfaces of the roof are 

-g ~ ~0 x:o = rEHs - ho(01x=o - 7".,) (5) 

and 

00 .... - g ?x = hi(OI .... - OR). (6) 

On account of their periodic natures, solar insolation 

and ambient air temperature can be Fourier analysed 

in the form 

oc 

H~ = ao + ~ a, exp(inwt) (7a) n=l 

and 

7", = bo + Z b, exp(inwt) (7b) n=l 

where the Fourier coefficients a, and b, are. in general. 

complex and can be expressed as 

a, = A, exp(-ia,) 

and 

b, = B, exp(-ia',). 

The value of A,. B,. a, and a', corresponding to 

19 June. 1979 in Delhi are given in Tables 3 and 4; 

further 

o3 = 2nlperiod. 

In view of equation (1), the boundary conditions (5) 

and (6) and the periodic nature of H~ and T. one can 

assume the following periodic solution 

O(x.t) = Ax + B+ ~ {c, exp(fl, x) n=l 

+ D, exp(-fl,x)}exp(inwt) (8) 

where 

/~. = -~o,,~(1 + i) 

and 

=(wpc~ 1:2 

~o \ T£ / 

The water temperature as a function of y and the 

constants A, B. c. and D. can be obtained from 

equations (4)-(6) with initial condition 

at y=0; Tw=Tt 

where 

T~ = Tto + ~ tin exp(inwt) (9) n=l 

ttN= Tm exp(-ia~) 

T~N and a; can be obtained from Fou

knowing the time dependence 

temperature. 

Assuming the water temperature 

periodic function of t, one has 

T., = Two(Y) + Z Tw.(y)exp

n=l 

In order to evaluate Two(Y) and 

substitute the value of Tw from equat

tions (4)-(6); thus 

(i) time independent part 

~Two -- - ct'~y. 

R1 - Two 

After integration and using initial bou

at y = 0 i.e. equation (9), one gets 

Two(Y) = R'1 - (R'1 - Tto)e

and similarly 

(ii) time dependent part 

T.,.(y) = R s - (R s - Tm)e

where 

R', = [r'a° + M3h° + - H'b° M-4ho - R

#lwCw J 

A = MI + M2Two(y) 

B = M 3 + M4Two(y ) 

F hi(hoOn - "c2ao) 

M, = Lho(h~ + Ki+~K] 

I hoh, ] M 2 = - ho(hix I +K)+ hiK 

= VKhiOR + r2ao(hix, +K!] 

M3 L ~o(h,xl + K) + h,K J 

V ho(hixt + K) 1 

M4 = Lho(h~ ~ IQ + hiK 

and 

c.=-R,o(l-Kh--~ifl.)exp(-fl.

Dn = -Rlo(l + Kh--~-ifln)exp(flnX

Rio = R2o + R3oTwn 

R2o = 

r:a./Kl3. 

ho _ hi ho • ( l- (,+ 
7

3. Question to the NRC ACRS about WGOTHIC validation for Rev 19 Containment Pressure 

Calculations

QUESTION: Did the NRC review how the difference between:

(i) the Passive Containment Cooling System Large Scale Test (PCS LST) test situation, in 

which solar insolation (the presence of sunlight, i.e., solar radiation) aided evaporation, 

and

(ii) the situation to which the AP1000 computer-based safety analysis (using the WGOTHIC 

computer code) applies, in which the wetted surface is not exposed to sunlight and solar 

insolation does not aid evaporation, 

is accounted for when appealing to the PCS LST experimental test results to validate the use of the

WGOTHIC computer code analyses for predicting the effectiveness of the PCS in reducing 

containment pressure? Radiative effects act in addition to convection and conduction, and affect 

the calculated peak containment pressure. 
8

I note that the analysis for Rev 19 shows that the margins on containment pressure have been 

further narrowed to the point of almost vanishing, even after much so-called "pencil sharpening" 

(taking credit for things for which credit was not previously taken). 

Can the ACRS Committee members say whether, and, if so, how, the effects of solar insolation 

were quantified and subtracted from the LST test results when using the PCS LST to validate the 

WGOTHIC results for use in the AP1000 design certification? Or, whether this dissimilarity 

between the test and the situation about which WGOTHIC is being used to make predictions in the 

safety analysis is accounted for in some other way? If not, can you indicate what the NRC staff

ought to do (or require of the applicants) concerning quantifying these effects to determine how 

they would change the NRC's safety evaluation of Rev 19 of the AP1000 safety analysis? 

4. Concluding remark on significance of the question

Put briefly, the question above arises because it appears that on the AP1000 a scale model test of 

evaporative effectiveness performed outdoors in sunlight was used to validate predictions for a

process that does not occur in the presence of sunlight. (I.e., a computer program was validated 

for the purpose of predicting quantitative values arising from a physical process in which 

evaporation is important and that occurs in the absence of sunlight, using a scale model test that 

was performed in the presence of sunlight.) I emphasize that the factor that was neglected is a 

matter of basic science, not a matter of interpretation or analysis methodology. 

Put in terms of an everyday example, it seems to me that this would be akin to validating computer 

model predictions for a device that its manufacturer claims will rapidly dry clothing indoors in a 

darkened room, by constructing a physical model of the device and setting it outdoors in sunlight. 

That is, saying that the PCS LST scale model test validates the predictions of a WGOTHIC 

computer analyses of the effectiveness of the PCS in removing heat via evaporative heat losses is 

analogous to referring to the experimental tests of a clothes-drying device from data collected on a 

model of it used while outdoors in the sun, and then saying: look, my computer predictions were 

confirmed and I have thus proved how speedily this device works! My computer model 

calculations predicting how quickly water will evaporate when using this device indoors in the dark 

are now validated! 

S G Sterrett

Special Faculty - Research Associate

Department of Philosophy

135 Baker Hall

Carnegie-Mellon University 

Pittsburgh PA 15213

Attachment -- Reference 4 is an attachment to this letter.
Remarks by S G Sterrett, Carnegie-Mellon University, Pittsburgh PA

(slide images have been incorporated into the text below)

(to accompany slideshow of SterrettSlidesACRSMeeting16August2011.pdf )

[conveyed via telephone from Pittsburgh around 3:50 pm on August 16th, 2011 

to the meeting of the ACRS (Advisory Commitee on Reactor Safeguards)

Subcommittee on the AP1000, held at the Nuclear Regulatory Commission

headquarters in Rockville, MD]

Thank you for allowing me time to speak today. 

For the record, this is Dr Susan G Sterrett, of Carnegie Mellon University. Prior to 

my academic career, I worked in the nuclear power industry, including work in 

structural mechanics and work in fluid systems design. Although I did some work on 

Westinghouse passive plant designs, I never worked specifically on the AP1000. I 

obtained the information referred to here from the materials made available to the 

public on the NRC's website. 

ACRS members have been given two letters laying out detailed reasoning and 

technical references for the two issues I raise; my oral remarks will be brief 

summaries. 

 

 
 

In the midst of the severe heat waves our nation has been experiencing this 

summer, there have been news reports of road and bridge surface temperatures 

exceeding 140 degrees F, of airports that have closed because their concrete 

runways buckled1, of concrete roads, ramps, and bridges that have buckled2 3 4 5, 

and of water pipes across the US that have burst open from thermal loads6 . These 

effects remind us of the powerful effects of the sun because they are effects that are

not due to air temperatures alone, but to the effects of sunlight heating up surfaces, 

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 1 "Tim McClung with the Iowa Department of Transportation's Office of Aviation said at least two airports have reported buckling 

concrete runways, shutting down both." http://journalstar.com/news/state-and-regional/nebraska/article_c4dca640-2d40-52eb-b3e8-

e48a84962414.html#ixzz1V6JhQXaW viewed on August 15, 2011. 2 http://www.myfoxdfw.com/dpp/traffic/080311-heat-causes-roads-to-buckle. The high temperatures were a surprise to many, and 

are known only because of sensors put in for another reason: "Lege said the NTTA roadway sensors were originally installed to 

detect problems in freezing temperatures. She never imagined they'd record such high measurements." Read more on 

myFOXdfw.com: http://www.myfoxdfw.com/dpp/traffic/080311-heat-causes-roads-to-buckle#ixzz1V6IQGmua viewed on August 15, 

2011. 

3 http://www.youtube.com/watch?v=J8RIcnC6kcA

4 "Excessive heat also will cause concrete to expand, which can lead to buckling along roads, bridges, sidewalks and other 

thoroughfares made of the material." http://www.constructionequipmentguide.com/Midwest-Roads-and-Rails-Buckle-Under-IntenseHeat/16696/ 

5 There are far too many events of concrete roads, bridges, and other structures buckling in the heat this year (summer 2011) to list. 

They have occurred across the nation, from the southern regions in Texas to the northern ones in Wisconsin, and lots of places in 

between. Articles reporting these events can easily be located using a search engine for items in the "news" category, and limiting 

the search to the past few months. 

6 http://www.cnn.com/2011/US/08/13/water.infrastructure/index.html
i.e, of solar thermal radiation. There is a heat influx due to the sun that is not 

captured by considering air temperatures alone. Correct engineering design and 

analysis must recognize that. 

The problem is that the AP1000 analysis seems to have forgotten about the sun. 

Today I want to talk about how this error -- this false assumption -- affected rev 19 

calculations. The error must be corrected, and today I will try to explain why. 
--------------------------------------------------------------------------------------------------------------

"Forgetting about the sun Issue #1

--------------------------------------------------------------------------------------

-- The calculations of thermal loads on the shield building in the rev 19 

documentation submitted to the NRC reveal that a false assumption had to have 

been employed, since the maximum temperature used in the calculations is never 

higher than the maximum ambient air temperature, nor lower than the minimum 

ambient air temperature. Whereas, we know that the building exterior surface can 

get hotter than the ambient air due to solar radiation -- much hotter -- and that it can 

get much cooler than the ambient air due to radiation to the night sky. 

-- It is important to understand the significance of this error; I worry that the NRC 

staff does not understand that many calculations are affected by this false 

assumption, not just the concrete temperatures. The safety significance is the role 

of the heat input from the sun -- it is a flux, a heat RATE, into the reactor building, not 

merely an initial temperature condition. I've listed some affected calculations on the 

slide; notice that peak containment pressure is one of them. Heat transfer to and 

from the reactor building is a very important factor in the safety analysis of this 

passive plant. Throughout all of the AP1000 supporting technical documents I have 

seen, I have not once seen the radiative heat fluxes from the sun or to the night sky 

depicted. They are important to the conclusions of the safety evaluation of the 

effectiveness of the Passive Containment Cooling System in removing decay heat in 

an accident situation. This must be corrected. 
Here is the applicant's sketch of an AP1000 on a sunny day. There is a nuclear 

fission reactor inside the shield building. There is also the nuclear fusion reactor 92 

million miles away. Both are sources of heat input. 

The error I am pointing out is a simple matter of basic physics: The sun shining on 

the AP1000 reactor building will add heat to it by the mechanism of thermal radiation; 

by the same mechanism of thermal radiation working in the opposite direction, the 

AP1000 reactor building will lose heat to the night sky. These thermal transfers are 

in addition to heat transfer due to convection and conduction. It is that simple. Yet 

this simple fact seems not to be reflected in the AP1000 calculations. It seems to 

be missing from analyses sketches setting up heat balances that are used to derive 

equations or upon which reasoning of all sorts, including reasoning from 

experimental test results, is based. 
It leads one to ask: is it just the understanding of the effect of solar radiation on the 

shield building that is affected by the error of forgetting about the sun? The answer 

is no. That leads to issue #2. 

--------------------------------------------------------------------------------------------------------------

"Forgetting about the sun Issue #2: 

-------------------------------------------------------------------------------------

 

 

According to the applicant's submittal of the rev 19 changes, the peak containment 

pressure, which is extremely important to public safety, was calculated using the 

WGOTHIC computer code. Keeping peak containment pressure sufficiently low to 

protect the public relies upon evaporative cooling of the steel containment, which is 

wetted by flow from the Passive Containment Cooling System. The steel 

containment is located inside the concrete shield building. 
As explained in the rev 19 submittal, WGOTHIC was validated using a physical 

model test in which the dome was wetted -- but this experimental test appears to 

have been run outdoors, in the sun. I could find no discussion of, nor any 

recognition of, the significance of this difference between the experimental setup and 

the situation for which the calculations were made. 

 

 

The side by side pictures on this slide may help make the point clear: "The test 

setup used to validate the applicant's WGOTHIC computer code (i.e., the 

methodology of calculation of evaporative losses and of peak containment pressure) 

is pictured on the left; the situation for which WGOTHIC was used for calculations is 

on the right. 

One is in the sun -- the other is not. Evaporation in the test model will be aided by

the sun. Since WGOTHIC was validated using this model, the tendency may be for 
WGOTHIC to overestimate evaporative losses and thereby to underestimate peak 

containment pressure. What, if anything, was done to account for this? From 

photographs the applicant submitted, it appears that the small-scale test facility was 

out in the sun, too, so agreement between those two tests doesn't aid us in 

answering this question. The same questions apply to analyses by the NRC staff 

using the NRC's own computer codes. 

 

 

These two issues are important. One is important to the structural integrity of the 

shield building, which supports the water tank for the passive containment cooling 

system. Both are important for predicting the heat removal capability of the passive 

containment cooling system to remove decay heat after an accident. 

More hangs on keeping the containment cooled in this passive plant design than on 

other PWRs: I remind you that there is no core catcher on the AP1000. I remind you 

that, unlike other PWRs, the concrete shield building does not function as an airtight 

secondary containment on the AP1000, backing up the steel containment. The 
containment integrity plays a much more important role in ensuring public safety, so 

public safety depends heavily on the passive containment cooling system being able 

to remove decay heat. I have just explained to you that the analysis and 

interpretation of test results upon which claims of its ability to do so are predicated 

are incorrect. 

You have the opportunity to do something about what is certainly a serious omission, 

and what might be a error that has serious consequences. 

Here is why it is so important that you do so now: the only check and balance left at 

this point in the 10CFR52 process are the ITAACS7 and the ITAACS -- the criteria 

the system capabilities have to meet to be deemed acceptable, such as flowrates ---

were developed based on the same false assumptions. The ITAAC for the PCS heat 

removal capability is stated just in terms of providing a certain flowrate, not in terms 

of demonstrating actual heat removal capability in a realistic environmental context. 

The ITAACs will NOT provide a check on this error, and so won't necessarily indicate 

whether or not this omission meant that the safety systems won't be able to remove 

a sufficient amount of decay heat using the passive containment cooling system. 

Neither the structural testing of component capabilities nor the ITAACS are designed 

to let you know that this kind of error -- forgetting about the sun --- has serious safety 

consequences. 

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 7!!ITAACS!stands!for!Inspection,!tests,!analysis!and!acceptance!criteria.!!The!rule!

governing!how!this!only!remaining!step!after!Design!Certification!and!COL!issuance,!

prior!to!plant!operation!is!still!undergoing!change:!!

http://www.federalregister.gov/articles/2011/05/13/2011H11678/draftH

regulatoryHguideHguidanceHforHitaacHclosure
You don't want to find out that this serious omission does in fact have serious 

consequences via a serious accident. I don't, at least. I urge this committee to use 

whatever means it has to try and get this error corrected now. This might really be 

the last opportunity for anyone to do so. 

Thank you. 
Dept of Philosophy

135 Baker Hall

Carnegie Mellon University 

Pittsburgh PA 15213

July 7, 2011

Billy Gleaves, Sr Project Manager

AP1000 Projects Branch 2

Division of New Reactor Licensing 

Office of New Reactors 

Nuclear Regulatory Commission

Rockville, Maryland 20852

References: 

1. Memorandum from Billy Gleaves, Sr Project Manager, AP1000 Project Branch 2, NRO/DNRL to Eileen 

McKenna, Chief, AP1000 Projects Branch 2, NRO/DNRL dated June 21, 2011. "PUBLIC MEETING WITH 

WESTINGHOUSE ELECTRIC COMPANY ON THE AP1000 DESIGN CERTIFICATION – SHIELD BUILDING 

ROOF PASSIVE CONTAINMENT COOLING WATER STORAGE TANK ANALYSIS"

2. Materials (slides) prepared by Westinghouse for subject meeting, entitled "AP1000 Shield Building Roof 

PCS Water Storage Tank - June 30, 2011" (included in pdf format as Attachment I)

3. APPENDIX 3H "AUXILIARY AND SHIELD BUILDING CRITICAL SECTIONS", AP1000 Design Control 

Document, Revision 19, Westinghouse Electric Corporation.

(http://pbadupws.nrc.gov/docs/ML1117/ML11171A441.pdf)

4. "Guide for Estimating Differences in Building Heating and Cooling Energy Due to Changes in Reflectance 

of a Low-Sloped Roof", ORNL-6527, by E. I. Griggs, T. R. Sharp, and J. M. MacDonald, for Oak Ridge 

National Laboratory, August 1989.

( http://epminst.us/otherEBER/ornl6527.pdf )

5. "A Computer Model to Predict the Surface Temperature and Time-of-Wetness of Concrete Pavements and 

Bridge Decks", by Dale P. Bentz, August 2000. National Institute of Standards and Technology Report No. 

NISTIR 6551 (http://fire.nist.gov/bfrlpubs/build00/PDF/b00037.pdf )

SUBJECT: Thermal loads and effects due to radiative heating and cooling of AP1000 shield 

building exterior surface, which are in addition to all thermal loads and effects due 

to ambient air temperature. 

(Written question submitted in regard to: PUBLIC MEETING WITH WESTINGHOUSE 

ELECTRIC COMPANY ON THE AP1000 DESIGN CERTIFICATION – SHIELD 

BUILDING ROOF PASSIVE CONTAINMENT COOLING WATER STORAGE TANK 

ANALYSIS on June 30, 2011) 

I. Background

II. Technical Discussion

III. Relevance to AP1000 meeting topic of including thermal loads

IV. Question addressed to NRC by means of this letter
1. Background

In the subject meeting held on the morning of 30 June 2011, the topic of thermal loads on the AP1000

shield building was discussed, in that the presentation stated that the AP1000 DCD had been revised (from 

rev 18 to rev 19) to include thermal loads in some load combinations used in the shield building roof 

analysis. I raised a question as to the variety of thermal loads and effects that the term "thermal loads" was 

meant to include. The purpose of this letter is to follow up on one aspect of that question -- how surface 

radiative gains and losses were computed -- by providing more detail. In doing so, I have made a special 

effort to cite references from sources that are both readily available on the internet and whose authority I 

expect all involved would accept without question. 

Slides for the meeting were provided in pdf format, which are extremely helpful (included in Attachment 1, 

for convenience). On slide 8, the first bullet notes that in its review of rev 18, the NRC had ". . . requested 

Westinghouse to provide additional justification to demonstrate that the load combination 

requirements for inclusion of thermal loads were satisfied." During the meeting, it was stated that 

details about the thermal loads considered could be found in Appendices 3G and 3H of rev 19 of the 

AP1000 DCD. 

2. Technical Discussion 

Referring to the table 3H.5-1 "NUCLEAR ISLAND: DESIGN TEMPERATURES FOR THERMAL 

GRADIENT" On page 3H-24 of Appendix 3H of rev 19 of the AP1000 DCD (Ref, 3, downloaded from 

http://pbadupws.nrc.gov/docs/ML1117/ML11171A441.pdf on 6 July 2011), it can be seen immediately that 

the outside surface temperatures considered never exceed the maximum ambient air temperature and are 

never less than the minimum ambient air temperature. This indicates that the analyses and/or 

calculations of roof and wall surface temperatures are incorrect. Here is why: Thermal inputs to and 

thermal losses from a roof located outdoors will occur due to all three heat transfer processes: convection, 

conduction, and radiation. Temperature effects arise not only from the fact that the ambient air is at a

certain temperature, but also from the fact that there is radiative heating of the surface of a roof from the sun 

during the day and radiative losses from the surface of the roof to the sky at night. 

In response to this point, which I brought up at the meeting, someone in the meeting mentioned that "diurnal 

changes" were included. Now, it is true that the diurnal changes in the ambient temperature are, ultimately, 

due to radiative gains and losses of the earth's surface. However, these diurnal changes in ambient air
temperature do not include the changes in roof surface temperatures due to the radiative gains and losses. 

The topic of radiative heating and cooling of exterior surfaces of building and structures does not seem to be 

mentioned in the sections of the AP1000 DCD relevant to the analysis discussed in the meeting of 30 June 

2011. Nor did the participants in the discussion from industry or the NRC during the public meeting seem 

to recognize that this deficiency or error in the analysis presented in rev 19 of the DCD existed. 

Another comment made at the meeting was that solar radiation would "help." I assume the speaker meant 

that increased temperatures would result in reduced peak containment pressure. I understand that point, 

which may well be true, but even if it is true, it does not mean that shield building radiative gains and losses 

can be neglected, for two reasons: (i) radiative losses can cause the minimum temperature to be lower than 

the ambient air temperature, which, by the same token, might increase peak containment pressure, and (ii) 

there are other design considerations, such as limits due to structural effects, that need to be considered 

besides the limit on peak containment pressure. The additional temperature rise is not of the magnitude 

that it can be dismissed as insignificant. Its magnitude depends on the features of the surface, but it could 

easily be 20 or 30 degrees F additional temperature rise above the ambient air temperature for a 

concretized surface in a southern latitude. 

The role of radiative gains and losses from building surfaces is explained more precisely in many basic 

references on roof engineering; to cite a paper that specifically discusses the situation of an external 

concrete roof surface exposed to the outside atmosphere from an organization whose technical authority on 

this matter I trust you will agree to recognize, I refer to a report from Oak Ridge National Laboratories' 

Energy Division "Guide for Estimating Differences in Building Heating and Cooling Energy Due to Changes 

in Solar Reflectance of a Low-Sloped Roof" (ORNL-6257, Ref. 4 ). On page 13, we find the following 

comments that I hope will make the point that roof surfaces can get hotter than the ambient air during the 

day, and cooler than the ambient air at night: 

" A roof surface radiates infared energy to the sky and the surroundings. During the day 

incident solar energy more than makes up for this infared radiation, and a roof can be 

heated well above the ambient air temperature. During the evening, however, with no solar 

radiation, the loss of radiant energy to the sky can cool a roof below the ambient air 

temperature. Evening surface temperatures 20 [degrees] F below air temperature on clear, 

low humidity nights are common for well insulated roofs. " (p. 13, ref. 4 )

From another source I trust you will accept, I cite the NIST report "A Computer Model to Predict the Surface 

Temperature and Time-of-Wetness of Concrete Pavement and Bridge Decks" (Section 3.1 of ref. 5 ):

 

"[. . .] during the day, the concrete surface temperature generally rises above the ambient 

temperature due to the incoming solar radiation. At night, the concrete temperature falls due to 
radiation from the concrete surface to the sky, sometimes falling below the ambient air temperature 

and occasionally falling below the dewpoint. " (ref. 5, p. 5)

3. Relevance to AP1000 meeting topic of including thermal loads

In the June 30, 2011 morning meeting, the NRC staff stated that they are still evaluating the information 

submitted in rev 19 of the AP1000 DCD. As explained above, the thermal loads reported in rev 19 cannot 

be correct. The NRC staff should examine the methodology and calculations of temperatures and thermal 

loads provided in the DCD in light of the above points, all of which are a matter of very basic science and 

not a matter of opinion, convention, or interpretation. 

These additional temperature changes will add to the thermal gradients currently listed in rev 19 of the 

AP1000 DCD, which may add to the stresses and thermal loads. Since the correct temperature range is 

larger at both ends than the values reported in rev 19 of the DCD (the correct lows are lower and the correct 

highs are higher) the effect on the calculation of peak containment pressure cannot be dismissed by saying 

it "will help"; the corrected value for calculated peak containment pressure could increase, as well. 

There may be other design limits and licensing commitments that need to be reviewed, to see how

calculated magnitudes are affected by using the corrected temperatures and thermal loads. One limit 

mentioned in the meeting was thermal stresses and loads due to any differences in coefficients of thermal 

expansion between different materials; perhaps whether material properties at extreme temperatures using 

corrected values are the same as the values used needs to be examined, etc. The NRC staff doing detailed 

reviews are in a better position to identify these than I am; I note only that of course any other ones affected

should be identified and reviewed as well. 

4. Question addressed to the NRC by means of this letter

Question: From the considerations in this letter, it is clear that the values of the temperatures and 

thermal gradients reported in rev 19 of the DCD cannot be correct. I have indicated some 

corrections that need to be made to the analyses. These considerations also raise a larger question 

as to whether any of the other analyses and rationales for the AP1000 safety and nonsafety analysis 

that involved exterior building temperatures directly or indirectly used an inappropriate 

methodology. Can you please inform me as to how the NRC plans to handle the error identified 

herein? 
Sincerely, 

Dr S G Sterrett

Special Faculty - Research Associate 

Department of Philosophy

Carnegie-Mellon University 

Pittsburgh PA