ML23319A260

10-25-2023 Public Meeting Transcript - Increased Enrichment Regulatory Basis

ML23319A260
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Issue date:	10/25/2023
From:	Office of Nuclear Material Safety and Safeguards
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Download: ML23319A260 (53)

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ADAMS Accession No. ML23319A260 Increased Enrichment Regulatory Basis Public Meeting-20231025_130021-Meeting Recording October 25, 2023, 5:00PM 2h 0m 45s Philip Benavides 0:06 Good afternoon everyone. Im Phil Benavides. Im a project manager in the Office of Nuclear Material Safety and Safeguards, and I'm the project manager for the rulemaking on the increased enrichment of conventional and accident tolerant fuel designs for light water reactors.

Some of you in this meeting may recall at the public meeting we held on this topic on June 22nd of 2022.

We considered the feedback provided in that meeting and we've since developed a regulatory basis to support this rulemaking.

The regulatory basis was noticed in the Federal Register on September 8th, 2023.

I'd like to acknowledge our facilitators for today's meeting.

Carla Roque-Cruz and Daniel King, who will be helping us out when we get to the question portions of the meeting.

Slide 2 please.

The purpose of today's meeting is to provide stakeholders with information to facilitate comments on the regulatory basis, on increased enrichment of conventional and accident tolerant fuel designs for light water reactors.

I'd like to add that the NRC staff is not collecting comments on the regulatory basis during this meeting. Rather, towards the end of our presentation, we will describe how to submit comments and get more information on the rulemaking dockets.

Slide 3, please.

For our agenda today, we'll run through some logistics for the meeting and then we'll have some opening remarks.

We'll give you some background information and status on the rulemaking and an overview of the regulatory basis and its recommendations.

We'll stop for questions at key points along the way.

We'll then show you how to find more information on the docket and tell you how to submit your comments on the docket.

After that, we'll go over the next steps for this rulemaking and then we'll conclude the meeting.

ADAMS Accession No. ML23319A260 Please note that the topic times are estimated and that depending on the participation level, the meeting could adjourn earlier than scheduled.

Slide 4 please.

I have a few logistical items to go over to help the meeting go more smoothly.

Please note that we are recording this meeting.

If you do not consent to being recorded, you may disconnect at this time. Because we are recording the meeting we asked that only one person speak at a time.

Please identify yourself and your organization when you start speaking, and please speak clearly as the meeting will also be transcribed into teams. At the appropriate times during the NRC staff presentation. We'll open it up to the members of the public for questions, and here's how that will work. All attendees will have the ability to mute and unmute. To reduce unnecessary background noise, please stay on mute when you are not speaking.

When we open up the meeting for questions, we will ask you to raise your hand if you would like to speak, and then we will call on you and you can unmute yourself.

To raise your hand, you can click on the icon in Microsoft Teams.

You should see that near the top of the window.

If you're joining us today by phone, you can raise your hand by pressing STAR 5.

When we call on you, you can unmute by clicking on the microphone button and Microsoft Teams.

If you're joining us by phone, you can unmute by pressing STAR 6.

You may also need to unmute your handset if you press the mute button there.

If you prefer, feel free to turn on your camera when speaking.

So for phone participants, again that is STAR 5 to raise your hand and STAR 6 to unmute.

You can remember which one is which because the hand has five fingers, STAR 5 to raise your hand and STAR 6 to unmute.

We won't be able to see the names for those on the phone, so we'll just identify you by the last two digits of your phone number.

Chat feature is enabled in today's meeting.

Please use it for asking questions if you prefer to do so, rather than speak your question or to let us know if there's something not working properly during the meeting.

Everything in this meeting will be done verbally, so it is captured in the recording.

Again, just raise your hand if you want to speak.

ADAMS Accession No. ML23319A260 The presentation will be shown via Microsoft Teams if you connected to the link to this meeting notice then you should see the slides.

Now you can also access the slides in our ADAMS system and accession number ML23290A267.

The slides have also been posted to the meeting notice on the NRC's public website.

We will try to call out each slide number as we advance the slides so attendees can follow along. One more quick note for those of you on the phone to include you on the list of attendees, please send an email to the meeting contact Phil Benavides. This my email address is philip.benavides@nrc.gov.

That's Philip, P H I L I P, period, B as in boy, E N A, V as in Victor, I, D as in David, E S at nrc.gov, just as you see it on the slide.

Slide 6 please.

Or slide 5 please.

At this time, we're gonna have some opening remarks.

I'd like to introduce Andrea Kock.

She is the deputy office director for engineering and the Office of Nuclear Reactor Regulation. Andrea.

Andrea Kock (She/Her/Hers) 4:46 Thanks Phil.

I was gonna start off with a little bit of background for anybody who is new to the increase enrichment rule making about how we got here and then finish up with just what we're looking to accomplish.

I'm gonna be brief because I'm really looking forward to the discussion today.

So thanks Phil for all of the opening information.

I want to thank everybody for joining us today to talk about the regulatory basis document for the increase enrichment rulemaking.

So if you have been tracking what's going on with this rulemaking, last year the Commission did approve staff proposal to initiate a rulemaking to address increased enrichment for fuel enriched above 5 weight percent U-235 we had at that time looked at our existing regulatory framework and it does support licensing from 5 up to 10 weight percent U-235, although in some cases some amendments would be needed.

So what we were trying to accomplish with this rulemaking is to be more efficient in

ADAMS Accession No. ML23319A260 our licensing processes without compromising safety and reducing the number of exemptions.

So once the Commission gave approval to move forward with the rulemaking, we did a comprehensive review of our regulations and guidance to look at areas where increased enrichment may create a conflict with the regulations.

And we did identify a couple areas that could be affected by increased enrichment.

You're going to hear about a lot of those today, so I won't cover them in detail.

The Commission also directed the staff to analyze the issue of fuel fragmentation, relocation and dispersal.

So you'll notice that that is part of the analysis in the regulatory basis.

So as I said, our goal with the regulatory basis is to describe and document the staff's assessment of the different alternatives that we can choose and addressing the issues that we've identified in the regulatory framework.

If you've read through the reg basis, the Staffs conclusion was that there's sufficient justification to proceed with rulemaking.

The other thing I wanted to note is that the regulatory basis is quite complex and detailed.

This was quite intentional, so we wanna make sure that we really have fulsome engagement with our stakeholders early on the issues.

But with that said, I did want to point out that nothing at this point is set in stone.

This is the regulatory basis stage of the rulemaking.

There will be additional opportunities to engage with us through proposed and final rulemaking stages.

And so what we're looking for from you is weighing all the pros and cons of the different alternatives.

I think we may find that there's no perfect option.

So what would be looking for is what's the best option and some of these cases taking into consideration things like transparency, level of safety and efficiency.

So we're really looking forward to hearing from you.

I will note that in order for today's meeting to be a success, it's going to require interaction with you, our stakeholders.

So we really wanna hear you.

So please, let's have a wholesome and fluid conversation today.

We're here to listen and take your input.

We're looking forward to that feedback.

ADAMS Accession No. ML23319A260 And then just one last note, we won't be collecting comments during today's meeting.

Official comments must be submitted in accordance with the instructions that were in the Federal Register Notice.

So with that, I'm going to turn it back over to Phil and I'm looking forward to hearing the discussions today.

Thank you.

Jason Piotter 8:21 You're muted, Phil.

Philip Benavides 8:22 Yep.

Sorry.

Yep.

Slide 6, please.

Yep, I just realized it.

Thank you.

So, well, we'll now roll into the NRC staff presentation and discuss the rulemaking process and status of this rulemaking.

Slide 7, please.

This slide shows our typical rulemaking process.

Rulemaking is highly energy develops its regulations.

We are still in the second box denoted by the star where we have issued the regulatory basis on September 8th and we are in the 75 day public comment period which will currently end November 22nd, 2023.

The written comments received during the comment public comment period will go on the docket for the rule.

The next two major steps are the publication the proposed rule and the publication of the final rule.

In the proposed rule, we will utilize the stakeholder interactions and comments received from the public on the regulatory basis during the development of the rule.

We will continue to provide opportunities for the public in this process. Upon publication of the proposed rule in the Federal Register.

You will have an opportunity to review the proposed rule and provide written

ADAMS Accession No. ML23319A260 comments to the NRC.

We expect to hold a public meeting during that public comment period as well.

Slide 8 please.

As a way to provide background on how we got to this point, I'd like to go back to the beginning when the issue was identified. Throughout the last few years, staff has seen an increase in interest from industry for the use of fuel enriched above 5 weight percent uranium-235, or U-235.

The NRC noted that although the current regulatory framework allows for licensing of fuel above 5 weight percent U-235, the use of this fuel may result in numerous exemption requests from licensees.

So as a proposed solution, the NRC staff began pursuing rulemaking rather than licensing by individual exemptions and in December of 2021, the staff provided to the Commission SECY-21-0109 requesting approval to begin the rulemaking process.

Slide 9 please.

In March of 2022, the Commission granted approval to begin the rule making process as described in the staff Requirements Memorandum for SECY-21-0109.

The purpose of this rulemaking effort is to provide a comprehensive review of regulations and guidance that may be impacted by the use of fuels and enriched above 5 weight percent U-235.

The Commission also specified several considerations to evaluate, in addition to what was specified in the rulemaking plan.

These are listed on the slide shown.

Specifically, the rule should apply to fuel enriched up to 20% or HALEU levels.

That staff should address fuel fragmentation, relocation and dispersal and take a risk informed approach and that we should also engage stakeholders to develop regulatory guidance and that we should evaluate to see if our schedule can be expedited by leveraging ongoing efforts.

Slide 10, please.

The NRC issued the regulatory basis on September 8th, 2023.

The regulatory basis is discussed as the regulatory issues and alternatives to resolve them considers legal policy and technical issues, considers costs, and benefits for each alternative, identifies the NRC staff, recommended alternative for most regulatory issues with FFRD being an outlier, which will wait for public input received during this public comment period.

Stakeholder involvement includes today's public meeting and the public comment

ADAMS Accession No. ML23319A260 period opened until November 22nd.

In an effort to be open, I also want to take this opportunity to mention that a request for public comment period extension has been received and is under consideration.

This has been docketed to regulations.gov. If granted the public comment period extension would be provided in a notice in the Federal Register.

Slide 11, please.

The regulatory basis discusses these technical topics, which can be described in detail by the NRC staff subject matter experts.

Elijah Dickson will discuss control room requirements in 10 CFR 50.67 and general design criteria 19.

Charley Peabody will discuss criticality accident requirements in 10 CFR 50.68.

Don Palmrose will discuss both uranium fuel cycle environmental data and 10 CFR 51.51 and environmental effects of transportation of fuel and waste in 10 CFR 51.52.

Jason Piotter will discuss general requirements for physical material packages and 10 CFR 71.55.

Joey Messina and Ashley Smith will discuss the topic of fuel dispersal, which is a part of fuel fragmentation relocation dispersal.

Slide 12, please.

With that, let's move on to the regulatory basis overview, where our subject matter experts will present each of these technical topics, our first speaker today is Charley Peabody, who will discuss critically accident requirements of 10 CFR 50.68. Charley.

Charley Peabody 13:16 Alright.

Thanks, Phil.

Next slide.

So I'm gonna discuss 10 CFR 50.68, which is actually a combination of not only that rule, but there's another criticality accident rule which preceded it, which was 10 CFR 70.24.

So 50.68 was issued in 1998 to allow certain exemptions to Part 70.24. The 70.24 initial rule required active criticality monitoring as well as our emergency planning requirements for evacuation and rehabitation of the spent fuel pool area during a criticality accident.

Those requirements were deemed burdensome by licensees.

So in the late 1980s and early 1990s, we began seeing exemptions where basically

ADAMS Accession No. ML23319A260 margin to sub criticality was credited as a means for not requiring active criticality monitoring.

Basically, it utilizes a k-effective acceptance criteria with required probability and confidence levels.

Next slide.

So yeah, I kinda put this nuclear engineering 101 slide in to kind of describe what k-effective is.

It's defined in the regulation as the ratio of neutron production over the combination of neutron absorption and leakage.

In plain language, it describes the neutron population change from one vision generation to the next.

The k-effective number also corresponds to criticality.

If you have a k-effective equal to 1, you have a critical chain reaction.

A k-effective greater than one, you would have a super critical reaction and a k-effective of less than one is a subcritical chain reaction.

Of course, for 50.68 purposes, we want margin to sub criticality.

So we want a k-effective value that is substantively less than one, and we determine that that number is typically for wet storage about a k-effective of 0.95 at 95%

probability and confidence.

Next slide.

So as I mentioned on one of the barriers was written on one of the previous slides, 50.68 does have a caveat.

In paragraph B, as in Bravo, 7 which does limit application of 50.68 to enrichments less than or equal to 5%.

So as part of this, we're considering alternatives to that.

The first one would be to note would be no action, maintain the 5% limit and process specific exemptions to either 70.24 or 50.68, whichever rule that the applicant is committed to.

A second alternative we considered was to increase the enrichment limit to 10 CFR 50.68(b)(7) to basically less than 20 percent weight U-235, which is the maximum value allowable by 50.64.

And finally, rulemaking, you know another rulemaking option which would remove the specific enrichment limit and instead replace it with the tech spec design feature limit.

ADAMS Accession No. ML23319A260 And that's the one that we're recommending.

Next slide.

The reason why we're recommending this is because it maintains the existing sub criticality margins at the same k-effective probability and confidence levels.

Even if you increase that, as long as you maintain the probability and confidence interval, we have the same, basically, statistical certainty that you're maintaining the safety acceptance criteria.

The criticality safety impacts will be addressed during the fuel transition license amendment process.

You know it will allow consideration of any low enriched uranium value up to 20 percent weight.

We've commissioned a study with Oak Ridge National Labs, which is, you know, determining the feasibility at enrichments in the basically 10%, 15%, and 20% range to get some data on that.

And then finally, I think and most importantly this pathway preserves 50.68(b) compliance for all the existing fleets without a back fit.

If we had changed the value then it would have been possible that some plants which are currently in compliance with 50.68 would no longer be in compliance.

But if we instead specify that value in their tech spec, we know that they're operating with a limit that's already been analyzed in our fuel transition layer process.

Next slide please.

Are there any specific questions on 50.68?

Daniel King 18:16 So with that, if you have any questions related to 50.68 in Charley's presentation, please raise your hand electronically.

So that'll be at the top of your screen.

If your own teams will be the hand raise feature with the small hand or by pressing STAR 6 if you're on the phone line and then once you're on, then we'll call you just unmute yourself.

Alternatively, you can utilize the chat feature, so if you have any questions, please do that at this time.

Charley Peabody 18:53 All right.

ADAMS Accession No. ML23319A260 I'm not seeing any questions, so I think I'm gonna turn it over to the next presenter.

I'll wait.

I do have a question.

Daniel King 19:03 Kalene.

Go ahead and mute yourself and ask your question please.

Kalene Walker 19:07 Alright, so you're saying that because the greater enrichment has not been analyzed for these, that you would just make licensed amendment request rather than make the allowance?

Through remaking.

Is that what you're recommending is to clarify what you just said?

Charley Peabody 19:23 Well, so yeah, I think I think I can clarify it in a slightly different way.

Like when we would get a license amendment process, a license amendment, to review it as part of that process the applicant would have to provide a justification as to why at their higher enrichment level they still meet the k-effective acceptance criteria of, I'll just use the 0.95 at 95% probability and confidence for wet storage.

They would have to show that even with the increased enrichment that they still meet that In reality this is like a best estimate plus uncertainty method.

So if you increase enrichment, you would have to have like a lower actual calculated k-effective because you would have a greater confidence interval right now.

Typically you see like an actual k-effective best estimate of about like you know 85%

to 90% and then the rest of the 7% up to 0.95 is that uncertainty recapture.

But basically, to more directly answer your question, when the licensee submits the license amendment, they provide an analysis with that.

In addition, we're like, I mentioned, we're commissioning a study with Oak Ridge to determine some initial feasibility with existing fuel technologies to just kind of give us a sanity check.

So that like what we see from the applicants is what we would expect to see.

Kalene Walker 20:59

ADAMS Accession No. ML23319A260 So if this rule making were allowed to just go through, there would not really be a technical basis to validate the safety of it and the licensees would not have to show it.

If you just like change the rule.

Charley Peabody 21:10 Well, so that would be like alternative one if a licensee wanted to use a higher enrichment which we've had a few applications where they have, they have to submit a specific exemption.

But like I said, they still have to demonstrate to the NRC in advance that at that higher enrichment, there's still meeting the k-effective acceptance criteria of 50.68.

So they basically have to reform their analysis for the higher enriched fuel.

Kalene Walker 21:41 And recommendation two.

Then it would just be.

There would be no analysis.

Charley Peabody 21:46 Well. No.

Well, there would the question under if we went under recommendation two would be like whether or not, so like let's say that hypothetically a licensee wanted to go to 10% enrichment.

That's where alternative or recommendation to. I'm sorry.

Alternative two would get a little confusing because if the rule specifies that you have to analyze it up to 20%, then do they still have to do that even though they're not going to utilize that?

We think that we get the best information from the plant specific analysis which are in the fuel transition process which again we review in advance of implementation.

Kalene Walker 22:33 I guess my point, you know, it's just that if you do rule making, alternative two and just increase the allowance, then that would kind of eliminate the requirement for licenses to have to justify it, is that is that correct thinking?

ADAMS Accession No. ML23319A260 Charley Peabody 22:53 Thats not, I mean, that technically a legal question.

Kalene Walker 23:00 If you just change the rule, say, you can drive.

Charley Peabody 23:03 So I don't wanna give like an official interpretation of the regulation, but no, the way that we're currently applying this rule like you have to specify it in advance.

Like even if you commit to 50.68, if a licensee wants to go away from 70.24 to 50.68, they have to provide a spent fuel pool criticality analysis to the NRC, which demonstrates that they meet the k-effective criteria 50.68 before we approve them and allow them to comply with the criticality safety Analysis Rule 50.68.

Kalene Walker 23:39 I'm not trying not to take up too much time, but if you're saying, let's say it's a speed limit, you're saying like you're only allowed to drive, you know 70 miles an hour and this rule making would allow people to drive 120 miles an hour.

And this is justifying the safety of driving at 120 miles an hour.

So if you just increase the speed limit without requiring all of that justification, and so people could slip in go 120 miles an hour anyway.

Charley Peabody 24:06 So yeah.

Kalene Walker 24:09 I'm just trying to understand it better.

Charley Peabody 24:09 So yeah, so I would argue that we're not actually increasing the speed limit because where the meat and potatoes of the safety impact of 50.68 is in the (b)2, (b)3 and (b)4 acceptance criteria for k-effective.

We're not proposing changing those.

Those are gonna be 0.95 at 95% confidence and probability for wet storage and.98

ADAMS Accession No. ML23319A260 at 95% probability in confidence for optimal moderate modernization or aqueous fog storage.

So like, you know, like the actual speeds that they're going are staying the same.

What kind of change under your analysis or under your analogy would be that, like the accuracy of the radar gun would change.

So like you know, if you were using a less accurate radar gun then to be sure that they were still not over the speed limit, you would have to have like a larger probability to that.

But again, you would still have to have your speed checked and we would still be doing that to the same ultimate standard.

We would just basically have a greater degree of analysis in making sure that there's not, you know, added uncertainty from the increased enrichment input.

Kalene Walker 25:38 I could ask more questions, but I'll let everyone move on.

Charley Peabody 25:42 OK, if we have time at the end, feel free to.

Does anyone else have a question on 50.68?

Kalene Walker 25:46 Thank you.

Charley Peabody 25:58 All right, take it away, Phil.

Philip Benavides 25:59 OK. Yeah.

With there being no more questions.

Let's move on to our next speaker, which is Don Palmrose, who will discuss environmental requirements in 10 CFR 51.51 and 10 CFR 51.52. Don.

Donald Palmrose 26:12 Yeah. Thank you.

Next slide please. OK.

ADAMS Accession No. ML23319A260 Because the uranium fuel cycle and the transportation fuel and waste are connected actions, the operation and nuclear power plants under the National Environmental Policy Act, or NEPA, the staff has previously performed generic and analysis dating back to the 1970s to evaluate the environmental effects of the uranium fuel cycle and the transportation of fuel and waste.

These evaluations are documented in WASH-1248 for the uranium field cycle and in WASH-1238 for the transportation of fuel and waste, along with other supporting documents.

This original analysis was for enrichment levels up to 4 weight percent U-235.

The uranium fuel cycle analysis was codified into 10 CFR 51.51 as Table S-3.

For the transportation and fuel and waste, the environmental effects were codified into 10 CFR 51.52 as Table S-4.

Subsequent staff evaluations expanded Table S-3 and S-4 were up to 5 weight percent U-235.

Of note for Table S-4, there are other conditions that must also be met, else a full description and detailed analysis of the transportation impacts would need to be performed as part of the licensing action.

The staff is performed additional analysis to extend the enrichment levels above 5 weight percent U-235.

This has been done in two documents.

The first is a study to support accident tolerant fuel deployment published in NUREG-2266, which is currently available for public comment until October 31st.

Additionally, advanced nuclear reactor generic environmental impact statement that is before the Commission for approval also addresses the uranium fuel cycle for up to 20 weight percent U-235. Until these documents are finalized, the current practice for addressing these environmental impacts continue as before, as shown in the last two sub bullets where the uranium fuel cycle evaluation would be on a case-by-case basis as we have done in prior new reactor applications and a full description and detailed analysis would need to be performed for the transportation fuel waste.

Next slide please.

The staff considered three alternatives for 51.51 and Table S-3.

The first is the current situation.

As I mentioned on the previous slide addressed the environmental effects on a case by case basis, the recommended alternative is to incorporate the updated evaluations in NUREG-2266 and the Advanced Reactor genetic Environmental Impact

ADAMS Accession No. ML23319A260 statement into the regulation by this rulemaking to the extent Table S-3 to the highest enrichment levels these analysis can support.

The third alternative would be not to codify the updated valuations, but to reference them for the environmental findings in individual licensing actions.

Next slide please.

The same 3 alternatives were also considered for 51.52 on Table S-4, again with the rulemaking recommending alternative two.

Since these are essentially the same as before I'm not going to go any further explanation.

That completes my presentation, so open for questions.

Daniel King 29:44 So as a reminder, please provide your questions by raising your hand.

If you're using Microsoft Teams or press STAR 6, if you're on the phone line and then we will call on you at that time and then you could also put your questions in the comment section and we can call that out as well.

Seeing no hands and no questions and chat.

Donald Palmrose 30:21 In that case, I'll turn it over to Jason.

Jason Piotter 30:26 OK. Thanks Don.

My name is Jason Piotter.

I am a senior mechanical engineer and senior program manager for ATF and advanced fuels in the Division of Fuel Management in the Office of Nuclear Material Safety and safeguards.

Next slide, please.

Actually, yeah. There we go.

For this particular effort, the division of Fuel Management reviewed applicable regulations in 10 CFR Part 71 and 72 to identify any areas where specific reference to fissile material enrichment levels was evident.

None of the regulations in Part 72 were identified with an enrichment limitations and the regulations in Part 71 do not reference or limit the enrichment levels of the fissile material except for 10 CFR 71.55(g).

ADAMS Accession No. ML23319A260 This provision in 71.55(g) allows an applicant for a certificate of compliance to utilize this exception to 10 CFR 71.55(b) and is only applicable to UF6 transport.

It specifies an enrichment limit of 5 weight percent U-235 for the UF6, which is not currently bound.

The range of the enrichment that applicants may choose to ship in their UFC transportation packages in the future.

Now the regulation in 71.55(b) requires that a single pack transportation package should be designed and constructed, and its content so limited it would be subcritical if water were to leak into the containment system.

This non mechanistic criticality analysis with moderation ensures criticality safety during transport in the event that the moderator leaks into the containment vessel.

This exception to 71.55 be contained in 71.55(g) codified a long-standing NRC in worldwide practice for evaluating water in leakage into UF6 packages. The NRC determined at that time that it was important to do this because it would maintain consistency with domestic and worldwide practice that there was operational experience that demonstrated safe shipment of physical material enriched to less than or equal to 5 weight percent U-235 and the necessity that transport an essential commodity.

Noting that this was put in place back in 2004. Now this particular exception for UF6 transportation packages can be used if all of the specific conditions in the regulation in 71.55(g) are met.

Next slide please.

So, absent using the exception that exists in 71.55(g) applicants for a certificate of compliance, have the option of evaluating fiscal material packages, including UF6 packages in a variety of ways.

As I already mentioned, they can use the provisions under 71.55(b), which is a fairly standard way to evaluate these packages.

That may require some changes to current packages designs, or perhaps require new package designs to accommodate these higher enrichments.

They may also seek an exemption in this particular case to 71.55(b) such that they don't have to consider the water in leakage as part of their evaluation.

Or they could use the provisions in 71.55(c).

Now, 71.55(c) also provides for an exception to the requirements of 71.55(b) if the applicant specifies that the package incorporates a special design feature to ensure that no single packaging error would permit leakage and that appropriate measures

ADAMS Accession No. ML23319A260 are taken before each shipment to ensure the containment system does not leak.

This exception also does not limit the enrichment of the package contents, so again something to note here that the regulations in 71.55 in general allow for transportation of fissile material without a limitation on enrichment.

There's that special exception obviously in 71.55(g), but noting that the enrichment level itself is not generally considered an impediment to being able to ship fissile material.

Next slide please.

So based on its evaluation, the staff identified 3 alternative actions at the NRC could take.

I think these look fairly familiar to what we've seen before in previous slides, but the first option is to do no action, right, to utilize the existing certificate of compliance options that I just discussed.

The second option would be to increase that enrichment limit up to 20 weight percent U-235 and the third option would be to remove the enrichment level limit all together.

Now, I'll note that there would be need to be a technical basis if we were to look at doing the alternative two and three, we would have to look at things like criticality, experience and criticality benchmarks at higher enrichments to pursue that path.

Next slide please.

So the staff at this time is recommending alternative one, no action.

To date industry plans communicated to the NRC have not indicated that there would be enough requests for package approvals for transporting UF6 enriched up to 20 weight percent to conclude that rulemaking will be the most efficient effective process to support package approvals.

I'll note here that all the alternatives that have been considered are nearly cost neutral overall in terms of implementation.

The final point I'd like to make here before I take questions is that we do have a question out in the FRN soliciting any additional information that stakeholders might want to bring to us that can identify what the demand signal might look like for additional packages that might change the thinking on the efficiency and effectiveness piece of this and where rulemaking would perhaps be beneficial.

I have been getting some feedback very recently from a variety of sources that talks about the potential for an increased demand signal.

However, what I'd like to note here is that those plans have not been officially

ADAMS Accession No. ML23319A260 communicated with the NRC and so we're asking as part of this effort and question is to try to again facilitate those discussions and try to get that information in so that we can make the best decision with respect to this particular aspect of the rulemaking. And with that, I'll open for questions.

Daniel King 37:10 So again, as a reminder, when you ask a question, please state your name and affiliation and utilize the hand raise feature in teams and by pressing STAR 6.

Al, please unmute yourself?

CSONTOS, Aladar 37:23 Thank you.

Yes, Jason, this is Al Csontos, Nuclear Energy Institute, NEI, and Jason on your last can you go back one slide?

So you talked about, you know, the UF6 here, those demand signals that you're talking about, were they for other, you know, a fuel form other than UF6?

We're only thinking about.

Are you thinking about other?

The question is, are you thinking about other fuel forms other than UF6 or is it just UF6?

Jason Piotter 37:57 So just as a preamble here. Al.

I was smiling because I was hoping you were on the call.

And were gonna ask me a question.

So thank you for that, because you're who I was thinking about even from the public meeting back in June.

What I'll say here is we're only looking at 71.55(g), right?

So that only affects UF6 packages at this point with respect to an enrichment limitation.

That doesn't mean that we don't have other technical, I would say, challenges to consider for other fuel forms or what have you.

But related to this specific rulemaking, we're only looking at UF6 and how it's affecting the UF6, it's part piece of the regulation.

ADAMS Accession No. ML23319A260 CSONTOS, Aladar 38:39 OK. Thank you that that, that helps.

Daniel King 38:52 Kalene.

You can go ahead and unmute yourself and ask your question.

Kalene Walker 38:57 So this means that you're not looking at transportation of the spent fuel and the considerations of higher burnup on spent fuel.

Jason Piotter 39:07 Well, this particular rulemaking the way that it was focused, it was looking at only specified enrichment limits that were in the regulation, not the overall issues that perhaps may be might exist on the spent fuel side.

So this would only be on the front end of the fuel cycle for transportation.

This particular action does not consider or include anything related to the back end for transportation.

Kalene Walker 39:33 Is your ATF rulemaking the high burnup and all, and the higher enrichment. Are any of them looking at the transportation of spent fuel or storage of spent fuel because your NUREG-2125 says that the time of the analysis it was the maximum burnup for the spent fuel for transport was 45 GW days.

So, and you're looking at.

I mean, obviously the higher enrichment is gonna create much higher burn up.

And so you're looking at, it seems to me you're looking at 10 CFR rules wherever it says enrichment.

You wanna change that rule but not assess all of the other things that assume that because of that the 5% limit you. I mean it's like you're playing to the test instead of testing to the rule as far as I'm concerned from the way I see it, you know it's a, correct me if I'm wrong, but there's a lot of assumptions going on here that all the other regulations will be met.

Just because you changed them where it actually says but.

ADAMS Accession No. ML23319A260 Jason Piotter 40:58 I fully understand your position Kalene.

What I will say is that yes, we are considering those things.

You know, we're not thinking about these things in silos.

This particular effort here is exclusively focused on the enrichment level limit that is specified within the regulation itself.

It does not draw any conclusions on whether or not there would not be downstream effects related to this, but for this particular rulemaking this is the focus based on the instructions that we received in the SRM and that was in the original SECY paper that was written.

Donald Palmrose 41:36 Hi calling this is this is Donald Palmrose, a senior reactor engineer in the environment COE.

We do cover that aspect of it in our environmental reviews, and that was one part that's being addressed in NUREG-2266 and also to a certain degree in the Advanced Nuclear Reactor, generic Environmental Impact statement.

But yeah, those kind of issues would be covered under the environmental review and the working assumption is that the spent fuels being chipped in certified transport packages as basis for that analysis.

Kalene Walker 42:18 OK, you know, I was looking at that 2266 and I was looking for spent fuel and it looked like it was about one paragraph that said, you're basically assuming that there won't be much difference with the lower burner.

So I'd really like to see where that is actually looked at.

I'm concerned about the current storage with the high burnup fuel and the hydrides at the NRC hasn't even really acknowledged the hydrates deterioration of the spent fuel in storage, never mind transportation.

So I think you're really potentially, extremely aggravating the spent fuel storage problem that a lot of people are concerned about.

Thank you.

Donald Palmrose 43:05

ADAMS Accession No. ML23319A260 Yeah.

The only thing I could add to that is that NUREG-2266 is still open for public comment on regulations.gov under NRC-2023-0113.

Kalene Walker 43:20 I'm aware of that.

Donald Palmrose 43:21 OK. Thank you.

Daniel King 43:31 I see no other questions in the chat or additional hand raise, so I think it's back to Jason and Phil.

Philip Benavides 43:43 Next slide please, Aaron.

With that, this is our schedule break for the afternoon.

With that, I have a time of 1:44.

Let's return in, let's say 1:55.

Alright, thank you.

Philip Benavides 55:05 I'm showing 1:55 eastern on my clock, so welcome back.

Welcome back from the break.

Hope everyone had a good break.

You know, Aaron, if we can go to the next slide.

With that.

Welcome back.

Let's continue with the regulatory basis overview, where Elijah Dickson will discuss control room requirements in 10 CFR 50.67 and general design criteria 19, Elijah.

Elijah Dickson 55:35 Thank you very much, Phil.

My name is Elijah Dickson.

I work in the Office of Nuclear Reactor Regulation and the Division of Risk

ADAMS Accession No. ML23319A260 Assessment within the Radiation Protection and consequence branch, and I'll be discussing a regulatory issues surrounding the control room design criteria of 10 CFR 50.67 and general design criteria 19 of Appendix A of 10 CFR Part 50. General design criteria 19 in 10 CFR 50.67(b)(2)(iii) provide specific dose-based criterion of five rem total effective dose equivalent, or TEDE, for demonstrating compliance where the acceptability of the control room design, the history of fuel utilization for the current large light water reactor fleet has seen a gradual progression towards higher fuel discharge burn ups and increased enrichments.

In general, there has been enough margin in the facilities design basis to accommodate the criterion even for power operates up to 120% of the originally licensed steady state thermal power levels.

Increased power levels, enrichment and subsequent fuel burnups have a multifaceted impact on the licensees analysis of record, computed design basis accident create a logical consequence analysis results.

A rule of thumb is that an increase in power level has a linear effect on these results.

The increase in uranium-235 enrichment necessary to reach desired burn up levels increases the numbers of fissions within the reactor core and proportionally increases these results.

The impact of higher burnup on these radiological consequence analysis results is nonlinear, where the abundance of different radionuclides peak at different burn up levels.

Therefore, depending on how the core is designed with increased enrichments of uranium-235 and operated at higher burnup levels to reach longer cycle times, the impact of the radiological consequences computed to demonstrate compliance with the control room design criteria would increase, and substantially decrease the retained margin maintained by licensees to provide operational flexibility. The NRC recognizes the challenges the licensees face to retain margin for operational flexibility purposes within their licensing basis and the small amount of margin to the control room design criteria itself.

The NRC does not want to unnecessarily penalize licensees for seeking increase enrichments that may then result in margin reductions, and thereby require licensees to perform potentially extensive analysis to demonstrate compliance without a commiserate increase in safety.

Next slide please.

Slide 30, I'll be providing a little bit of background behind the control room design

ADAMS Accession No. ML23319A260 criteria.

It's objective is to ensure that the design of the control room and its habitability systems allow for a habitable environment for operators to remain in the control room and not evacuate during an emergency.

Ideally, you can think of this as a short sleeve environment that is comfortable for them to perform their actions under both normal and accident conditions.

A little bit of history behind the control room design criteria.

It was initially developed really in the late 1960s, but then codified in the early 1970s under Appendix A of 10 CFR Part 50 and then later amended through the accident source term, it's 10 CFR 50.67.

The criterion didn't foresee how licensees currently operate their facilities and manage their fuel, consider fuel enrichments above 5 weight percent uranium-235, or maintain coherence with other regulations concerning the Commission's comprehensive radiation protection framework.

The next slide will be talking a little bit more about this framework.

Slide 31 please.

Effective radiological risk communication is an important role in this rulemaking effort.

Although the control room design criteria are distinct from the operational dose limits, the staff recognize the two concepts share some similarities.

Specifically, both the operational occupational exposure limit of 10 CFR Part 20 and the control room design criteria are numerically equivalent and use the same units of rem TEDE.

Accordingly, the staff recognize that there is a potential for confusion. Should the NRC modify the control room design criteria to a higher but still safe performance level.

Changes would not alter normal operational or emergency exposure limits controlled under 10 CFR Part 20 and 50.47, which is the emergency plans. An increase in the design criteria does not necessarily correlate to an actual increase in exposures before beyond design basis conditions and to provide a little more context as to the purpose of the control and design criteria.

I'm paraphrasing from the statements of consideration for the alternative source term of 10 CFR 50.67, and that the design basis accidents were not intended to be actual event sequences, but rather intended to be surrogates to enable deterministic evaluations of the response of plant engineered safety features.

ADAMS Accession No. ML23319A260 These accident analyses are intentionally conservative in order to address uncertainties and accident progression, fission product transport, and atmospheric dispersion.

The use of the five rem TEDE doesn't imply that this would be an acceptable exposure during emergency conditions, or that other radiation protection standards of Part 20 may not apply.

This criterion is provided only to assess the acceptability of a design provisions of protecting control and operators under postulated design basis accident conditions.

The standards for radiation protection against radiation under 10 CFR Part 20 are based in part on the recommendations of the International Commission of Radiological Protection, or ICRP.

In Part 20, the NRC applies the standards to all exposure situations, both normal and emergency conditions.

It also provides an explicit exemption, in which case compliance would limit the actions that may be necessary to protect the public health and safety, to provide reasonable assurance that adequate protection measures can and would be taken in a radiological emergency.

The NRC is established emergency planning regulations and Appendix E of 10 CFR Part 50, as well as 10 CFR 50.47 the emergency plan. These additional regulatory provisions bear on the control of occupational exposures during emergencies where means for controlling exposures shall include exposure guidelines consistent with the Environmental Protection agencies, emergency workers and lifesaving activity protected action guides. The EPAs guidance provides that dose is received of the under emergency conditions should be maintained as low as reasonably achievable or LARA and should to the extent practical, be limited to five rem.

It allows for higher radiation doses in order to assure protection of others and valuable property if the maximum risk permitted to workers is acceptably low and that the risks or costs to others is avoided.

The guidelines for actions to protect valuable property is 10 rem, where a lower dose is not practical, and the guidelines for actions for saving lives or protect large populations is 25 rem.

These guidelines are endorsed in 50.47(b)(11) and is consistent with the positions of 10 CFR Part 20.

As such, the control room design criteria, which is a figure of merit intended to assess the acceptability of a given control room design, is on the lower side of this

ADAMS Accession No. ML23319A260 range of recommended values.

Next slide please.

Now we'll go into the alternatives at the staff assessed, we assessed 3 different alternatives.

The first one is no action.

We would be maintaining the current regulatory framework.

We continue to revise existing guidance and update source terms and when data becomes available as well as update transport models on an ad hoc basis as research and resources become available, we plan to issue this work in reg guide 1.183 Rev 2 in fiscal year 2025.

Slide 33 please.

Alternative two is to pursue rulemaking to amend the control room design criteria and update the current regulatory guidance accordingly with revised assumptions and models and continue to maintain appropriate and prudent safety margin.

The staff has already assessed and identified a range of acceptable values based on sound regulatory and scientific recommendations.

We would also be initiating new research and analyses for the development of mechanistic transport models and re-baseline several other operational and human health assumptions in the regulatory guidance when performing the radiological consequence analyses. The plan will be to issue this work and Rev 2 of reg guide 1.183 in support of the amended control and design criteria.

Slide 34, please.

Alternative three can be considered our most research intensive effort.

We would be updating the current regulatory guidance with revised assumptions and models and continue to maintain appropriate and prudent safety margins.

Similar to alternative two, we would be initiating new research and analysis to develop mechanistic transport models and re-baseline several other operational and human health assumptions and we would be assessing other mathematical methods, computational and statistical approaches, to reduce unnecessary conservatism and provide for greater flexibility.

Plans to commence work would be wrapped up in reg guide 1.183 Rev 3 soon after Reg Guide 1.183 Rev 2 is issued.

On to slide 35 please.

Our recommendation is recommendation two and amended control room design criteria and revisions to applicable regulatory guidance considering risk information

ADAMS Accession No. ML23319A260 would be the cost beneficial, straightforward, durable and efficient path forward when licensing increase enrichments up to 20 percent uranium-235. Beneficial impacts and other regulations such as 50.59 and Part 20 would also be realized.

It is flexible enough to consider multiple approaches to amending the regulation and would provide options for generic resolution to these issues.

We would be inviting stakeholder participation in this decision affecting this regulatory area rather than on a case by case basis that would result from the current regulatory framework.

The staff would be able to utilize ample operating experience, scientific data, technical information, numerous recommendations from national and international organizations responsible for radiation protection standards, as well as regulatory precedents that would support the reevaluation of a control room design criteria.

With that, I would like to move on to slide 36.

We have two Federal Register notice, questions one and two, and I'll be paraphrasing here.

The first question is, would the numerical selection of a control and design criteria be better aligned with regulations designed to limit occupational exposures during an emergency or regulations designed to limit occupational exposures during normal operations?

And we would like you to please provide the basis for your answer, and then on to slide 37 please.

The next question is would a graded risk informed method for demonstrating compliance with the range of acceptable control and design criteria values be appropriate instead of a single selected value such as the current 5 rem total effective dose equivalent which would provide necessary flexibilities for current and future nuclear technologies with enrichments up to 20 weight percent and we would appreciate it if you also provide your basis for your response as well. With that, that is my presentation and I would be happy to take questions.

Daniel King 1:07:44 So as a reminder, please raise your hand electronically if you have a question, you can do so by pressing STAR 5.

If you're on the phone line or the hand raise feature on teams once called on, you can unmute yourself or press STAR 6 here on the phone line once called on.

ADAMS Accession No. ML23319A260 And as a reminder, please state your name and affiliation.

Also you can use the chat feature and we'll call on you that way as well.

I see we have a hand raised already.

Looks like Bradley.

Daniel King 1:08:13 You can unmute yourself.

Dolan, Bradley Wicker 1:08:16 Yes, you're calling on Bradley Dolan.

Daniel King 1:08:19 Yes, Bradley Dolan yes, you are correct.

Dolan, Bradley Wicker 1:08:21 OK, so I'm intrigued by that question 2.

I just wanted to ask for a little clarification.

So we've been guided to do this process in a risk informed manner.

It seems like that's what where this is going.

So what you're postulating here is perhaps you know for very remote events.

You know even 1 times 10 to the minus six kind of events.

Just hypothetically, maybe would be there would be 1 dose limit, maybe 25 rem and for more frequent higher frequency events, maybe there be some lower design dose limit, you know maybe 10 rem.

Is that kind of the big picture of what this is getting at?

Elijah Dickson 1:09:02 That's right.

Yeah.

So we're looking for, you know, these types of ideas.

Dolan, Bradley Wicker 1:09:07 OK.

Thank you.

Yeah.

ADAMS Accession No. ML23319A260 I think we'll follow up with that.

Just for clarification, I work for the Tennessee Valley Authority and I'm also currently the chairman of the Risk Management Committee of the PWR Owners Group.

Elijah Dickson 1:09:10 TVA Understood. OK.

Daniel King 1:09:21 Thank you.

Are there any other questions?

Please raise your hand.

If you have one or put it in the chat?

Al from NEI.

CSONTOS, Aladar 1:09:32 Just and Elijah. Yeah.

So you mentioned about the, can you go back two slides, I think.

So could be the thing. You had mentioned I think when you were on this slide about a process to discuss how, you know, because you asked a lot of basis, in terms of numbers or yeah for numbers are you looking in the response, the industrys response to the FRN question.

Actual proposed numbers to provide to NRC.

Or are you looking for more of a you know when you say basis, what do you mean by that?

What do you want?

A number and a basis.

Do you want a path that we can get to that we can discuss and have a dialogue?

Elijah Dickson 1:10:18 Yeah.

We're looking for.

Understood, understood.

We're looking for more than yes or no answers to these questions.

So we would like to have context in regards to what your responses to this question.

ADAMS Accession No. ML23319A260 CSONTOS, Aladar 1:10:32 OK, I think you know some of these are just, it's not as simple as just proposing a number.

It's more of a dialogue and a discussion. Yeah.

Elijah Dickson 1:10:38 Understood.

Yeah, that's right.

CSONTOS, Aladar 1:10:39 So that's what you had mentioned about the reg guide, updating a reg guide.

Is this something where, and it could be through the rulemaking process.

I'm not sure if we have that opportunity to have that dialogue, but having a dialogue, it's open and transparent, fully open to the public for their vetting and such is important to maybe get to some, you know, place that the numbers that are chosen to have a good basis and a good discussion prior to that.

Elijah Dickson 1:10:58 Mm-hmm.

That's right.

Yeah.

We plan on further engagement once we start to kick off rev two work here soon.

So reg guide 1.183 Rev 2 work that will be going on with that will be considered under the umbrella of increased enrichment and we'd be looking to maybe perhaps have, you know further public meetings or workshops to have these types of discussions in the future.

CSONTOS, Aladar 1:11:42 That would be helpful.

Thank you.

Daniel King 1:11:46 Thank you.

ADAMS Accession No. ML23319A260 And we have another hand raised.

Andrea, you can unmute yourself and state your affiliation.

Maioli, Andrea 1:11:53 Yeah.

So this is Andrea Maioli from Westinghouse.

Can you hear me?

Elijah Dickson 1:11:59 Yeah, I can hear you.

Maioli, Andrea 1:12:00 OK.

Thank you.

So it seems from your presentation that alternatives two and three you're really not potentially mutually exclusive, but possibly like combine but with different time scale like you're talking about Rev 2 or Form 113 and Rev 3.

Elijah Dickson 1:12:16 Yeah.

So the big distinction between alternative two and alternative three is that there would be no rulemaking in alternative three that we would jumpstart much more research in alternative three to you know assess other types of models, statistical approaches you know. In effect kind of redoing 60 years worth of traditional design basis accident analysis.

That's really what alternative 3 is.

With the intent of providing additional flexibility without any rulemaking.

Is that clear?

Alternative two would include the rulemaking and some research, yeah.

Maioli, Andrea 1:13:10 OK. Yeah.

Thank you.

Daniel King 1:13:16

ADAMS Accession No. ML23319A260 Thank you.

Are there any additional questions I'm seeing?

None in the chat.

I don't see any other hands raised so.

One final call if there are any additional questions on this topic.

Elijah Dickson 1:13:30 Thank you very much.

Daniel King 1:13:32 Thank you.

Back to Phil.

Philip Benavides 1:13:35 And I guess now next we'll move on to our next speakers where Joey Messina and Ashley Smith will discuss Fuel fragmentation, relocation and dispersal.

Ashley Smith 1:13:47 Hi, I'm Ashley Smith.

I'm a technical reviewer in the nuclear fuel and Methods Branch division of safety systems in the Office of Nuclear Reactor Regulation.

I'll be going through the first few slides of regarding fuel dispersal and then hand it off to Joey.

First I'm gonna discuss what fuel fragmentation, relocation and dispersal is.

High burnup experiments have shown that the fuel can fragment during a loss of coolant accident.

Differences in pressure across the cladding can lead to ballooning and bursts of the cladding.

The fragmented fuel can relocate into the balloon region and if first occurs, the fragments can disperse into the reactor coolant system.

Next slide.

This slide discusses the background in regulatory issue of fuel dispersal, the 50.46 acceptance criteria for loss of coolant accidents date back to 1974 when FRD were not known phenomena. Acceptable approaches to demonstrate compliance with the

ADAMS Accession No. ML23319A260 regulations have ensured that catastrophic failure of the rod structure and loss of fuel bundle configuration are precluded.

These approaches include annual assessments to show that peak cladding, temperature and maximum local oxidation remain below the limits of 50.46.

Fuel dispersal would be a departure from precedent because the fuel bundle geometry would be lost.

Fuel dispersal is not explicitly addressed in the current regulations.

Next slide.

The staff developed 5 alternative licensing pathways that could be pursued.

The five alternatives are not mutually inclusive or combinations of elements from multiple alternatives could be considered.

Staff is also open to considering other approaches not included in the five alternatives based on public comments. Joey is going to talk about the specifics of each alternative.

Joseph Messina 1:15:35 Next slide please.

So good afternoon.

My name is Joseph Messina.

I'll discuss the five lessons in pathways that we outlined in the regulatory basis for fuel dispersal.

To start off, we'll begin with the status quo and consider maintaining it as one of the licensing pathways.

In this alternative, we would keep the current regulatory framework mostly the same without any major updates and continue with the precedent that a significant amount of fuel dispersal should not occur.

Therefore, the most straightforward licensing approach under this pathway would be to demonstrate that the rod susceptible to fine fragmentation do not burst and thus lead to significant dispersal.

It is expected that technical solutions would be needed to prevent high burnup rods from bursting, such as changes to fuel design and/or core design.

Use of accident tolerant fuel may also help.

For example, coating the chromium cladding may limit the balloon size as well as the burst opening size.

But since the regulations do not explicitly speak to fuel dispersal, allowing significant

ADAMS Accession No. ML23319A260 dispersal may not technically require a change to the regulatory framework.

But this would lead to regulatory uncertainty and challenges for both industry and the NRC.

Therefore, pathways that consider significant dispersal are discussed as a part of the other alternatives.

Next slide please.

The second licensing pathway rethinks a 50.46a style modification of emergency core cooling system or ECS requirements. For those that are not familiar with the 50.46a rule it was a final rule that went to the Commission in 2010 that risk informed LOCAs.

Specifically, it established a transition break size for breaks smaller than the transition break size, LOCAs would be analyzed as they are today, but for breaks larger than the transition breaks size, less conservative assumptions and modeling could be employed, such as allowing credit for off-site power. In this licensing pathway, LOCAs above the transition break size would essentially be treated as beyond design basis.

In beyond design basis accident analysis, best estimate modeling and more realistic assumptions can be employed, while during typical design basis accident analysis, a 95/95 is a typical standard for modeling. The use of beyond design basis modeling may help to show that no rod susceptible to fine fragmentation end up bursting as a result of a LOCA, but it still may be challenging.

Therefore, this pathway could be combined with other pathways that analyze the consequences of dispersed fuel, and these pathways would be discussed in the coming slides.

There would be an obvious benefit outside to this alternative outside of FRD in LOCA analysis, such as increased margin to the peak clad temperature and oxidation limits are required in 50.46.

I'll note that this would not be a simple cut and paste from the 2010 rule.

This would be a modernization of the rule.

We can update it with any knowledge gained since 2010 or to better capture today's landscape.

Next slide please.

The third licensing pathway proposed in the regulatory basis is to provide a safety demonstration of post fuel dispersal consequences.

Phenomena such as coolability, recriticality and long-term cooling will need to be addressed like any other local phenomena.

That is to say that they will need to be modeled with 95/95 probability and

ADAMS Accession No. ML23319A260 confidence. As a part of this guidance would be developed regarding analysis of the consequences. We are sponsoring a phenomena identification and ranking table exercise or PIRT exercise on the consequences of fuel dispersal that is expected to be complete sometime early next year.

This PIRT would help us to issue guidance with the rule.

The guidance would have to be high level and conservative, though, since there has not been much experimental research on the consequences conducted to date.

But we envision that if this option is pursued, experimental research would be conducted in the long term that can be used to eventually update the initial guidance to be less conservative and more specific.

Next slide please.

The 4th licensing pathway would be to provide a generic bounding assessment of dose and use risk insights to address post fuel dispersal consequences.

Currently, there are dose criteria for most DBA's, but for the 50.46 LOCA that is mitigated, we assume that the consequences are bounded by the maximum hypothetical accident dose, which assumes an unmitigated LOCA that leads to a substantial melt of the core.

This is often referred to as the MHA LOCA and is used for a siting.

This option would establish a dose criterion for the LOCA analyze under 50.46 with dispersal, so a new dose criteria.

Licensees would need to demonstrate the ability to predict a source term for a LOCA with fuel dispersal or be directed to use a fraction of the MHA LOCA source term based on the amount of fuel that is predicted to be dispersed.

Regarding the other consequences of fuel dispersal, in this option we postulate that risk insights could be used to address them.

For example, insights from operating experience and other regulatory requirements and industry initiatives may be able to be used.

For example, the severe accident mitigation guidelines, the TMI action plan requirements and emergency operating procedures, to name a few.

Next slide please.

The 5th licensing pathway presented in the reg basis is to use probabilistic fracture mechanics to show that leaks in large pipes will be identified before failure, precluding the need to analyze ECCS performance during large break LOCAs.

This would be a major departure from current practice and would have implications outside of LOCA space as well.

ADAMS Accession No. ML23319A260 This licensing approach builds on industry initiatives such as EPRIs alternative licensing strategy.

This licensing pathway would use the extremely low probability of rupture code or xLPR code and the leak before break concept to show that leaks and large pipes will be able to be detected and operator action will be able to be taken to shut down the reactor with sufficient probability before a large pipe breaks and thus the large break LOCA occurs. If the large break LOCA does not occur it would prevent any rod failures and thus fuel dispersal from occurring.

This alternative also states that well if a large break LOCA does not occur then ECCS performance would not need to be analyzed.

We acknowledge that this alternative would have ripple effects outside of just the large break, LOCA, and we would examine these effects in more detail as we assess each option.

Next slide please.

So we provided 5 lessons in pathways in the regulatory basis, but at this time we do not provide a recommended pathway because we feel that stakeholder feedback is important before making such a decision. We provided 6 questions to the public in the FRN and Reg basis on fuel dispersal and the alternatives to better help us make a decision.

And I'll go over those in the next few slides.

But before I do so, I wanted to emphasize that as we previously stated, these alternatives are not mutually exclusive, will consider combinations of the alternatives presented or any proposed pathways that were not discussed.

I've heard it described as a sample space of options which I believe is a good description.

We provided some projected boundaries for the sample space and are considering options across the sample space and may even consider options outside of it as well.

Next slide please.

So now I'll read the six questions written in the FRN and Reg basis so that everyone's clear on them.

But this slide just has all the alternatives on one slide for visual ease.

Next slide, please.

So the first question is, are there any alternatives not described in Appendix F of the regulatory basis on FFRD that the NRC should consider?

Are there elements of alternatives presented, or other alternatives that the NRC

ADAMS Accession No. ML23319A260 should consider?

The second question is that stakeholders previously expressed concerns on the proposed 50.46a rule when it was initially proposed in 2010.

What concerns about 50.46a and alternative two which would modernize 50.46a exist in today's landscape.

Next slide please.

The third question is under alternative two as currently proposed in the regulatory basis, the staff would apply the regulatory precedent under which fuel dispersal that would challenge current regulatory requirements would not be permitted under LOCA conditions. Would the increase flexibilities gain from best estimate assumptions and methods employed during large break LOCA analysis make this alternative reasonable?

Question four.

What changes to plant operations, fuel designs or safety analysis tools and methods would be necessary under each proposed alternative.

Next slide please.

Question five.

Please provide any information that would be relevant to more accurately estimate cost associated with each proposed alternative.

And question six.

What are the pros and cons of each alternative, including the degree to which each alternative is consistent with the principles of good regulation. And I will emphasize that these are areas of interest that would be helpful for us to consider when moving forward in the proposed rule phase.

Next slide please.

And I'll take any questions.

Daniel King 1:26:31 So as a reminder for the question and answer period here.

Please raise your hand on teams by pressing the raise feature or by pressing STAR 5.

If you're on the phone line, once we call on you, please state your affiliation and your name and then you can obviously unmute yourself when you do that, and if you would like to, you could also put your question in the chat.

So I see we have a question from Ralph.

You can unmute yourself.

ADAMS Accession No. ML23319A260 State your affiliation and ask your question.

Ralph Meyer.

Cannot hear you at this time.

If you're having teams difficulties, you could also put your question in the chat.

As a reminder, please unmute yourself.

Ralph, are you able to unmute yourself at this time to ask your question?

OK, for the sake of time, we'll move on to Kalene and we'll come back to Ralph.

Ralph, feel free to put your question in the chat in the meantime, and we can address it. So Kalene feel free to unmute yourself.

Daniel King 1:27:51 State your affiliation and ask your question.

Kalene Walker 1:27:54 Kalene Walker.

I'm just a regular old person.

I live near a spent fuel facility.

That's why I'm deeply involved in understanding the spent fuel management of nuclear waste.

And I see how this is a very unresolved problem.

I'm wondering, and I've been on a lot of these meetings and I keep asking, if you had a large break LOCA in the reactor where you have FFRD, how are you going to handle that fuel?

Are you gonna put it into a pool and have all of this particulate matter go into the pool?

Who is looking at that part of the back end consequences of storing this waste for the next 100,000 years?

Joseph Messina 1:28:58 Yes Kalene. Thank you for your question.

We would most likely address if there's an accident, any accident clean up on a case by case basis.

Any fuel that, you know, any fuel dispersal would not simply be put into a spent fuel pool with all the other regular storage fuel.

ADAMS Accession No. ML23319A260 Kalene Walker 1:29:22 Could you tell me an option?

Give me an example of what would be a path forward for getting it out of the reactor.

Carla Roque-Cruz 1:29:33 I'm sorry.

Hi I just want to stress out.

This is Carla Roque-Cruz.

I work with the NRC and I'm one of the rulemaking PM's.

I just want to stress out that the meeting today, were really focusing to get questions related to the reg basis and clarifying questions.

So that you are able to provide your comments to the reg basis.

So we're not trying to have a technical meeting at this point.

So I just want to make sure that we know that the focus of the meeting is to clarify the reg basis, not necessarily to talk about the technical issue.

Thank you.

Kalene Walker 1:30:20 I'm kind of surprised at that response you just said.

If you could just reiterate what you said, the path forward would be if there was a large rate LOCA in the reactor.

Could you reiterate what you had just said to the previous responder?

Who just said you could you just say that again?

What you would do if there was a large break LOCA, where you would put, how you would take it out of the reactor and put it somewhere.

Joseph Messina 1:30:53 Well, right.

Right now I think this question when we discussed fuel dispersal in the regulatory basis, we are discussing the accident and before what happens before and during the accident and mitigating the accident.

I believe that this would be out of scope, but for example there are damaged fuel

ADAMS Accession No. ML23319A260 cans that would be, could be used for any, you know, damage fuel assemblies during an accident.

Kalene Walker 1:31:29 But currently the damage fuel cans are not intact containers.

They have, they have mesh, they don't, they wouldn't contain articles or chunks or gases.

Carla Roque-Cruz 1:31:45 And I just, in the interest of time and because I know we have a lot of interest on a direct basis and the comments that people want to be able to provide using the methods provided in the FRN.

Kalene Walker 1:31:59 I understand I keep getting on. Just if I could, I keep on getting on these calls and asking about the back end of fuel and I mean that's the most of an answer I've gotten which is not an answer so thank you.

Carla Roque-Cruz 1:32:14 And thank you so much.

Thank you so much, Miss Walker, for your comment.

And please remember that the FRN is out and it has all these the instructions on how you can provide comments on this document.

So if you have any further document, any further comments, I'm sorry.

Please send them to us using the methods that are described in the FRN next.

Kalene Walker 1:32:37 OK.

Well, my comment on this is I don't think you can regulate yourself out of an accident, so thank, OK.

Carla Roque-Cruz 1:32:45 Thanks.

I think I we have another hand raise.

ADAMS Accession No. ML23319A260 Daniel King 1:32:50 Yes.

So before we move on to Al, I want to see if Ralph Meyers still had a question.

If you do, feel free to raise your hand again and we'll come back to you.

But as of now, I don't see a question in the chat.

Ralph Meyer 1:33:05 Can you hear me now?

Daniel King 1:33:06 We can hear you now, so feel free to start your affiliation and ask your question.

Ralph Meyer 1:33:09 This is Ralph Meyer.

I'm retired NRC SLS and I worked with fuel behavior under accident conditions. I want to point out that there are some petition in front of the Commission now to replace the current 50.46 embrittlement criteria, namely the peak cladding temperature and the maximum oxidation limits, with some limit on the number of burst balloon rods in the core.

So the petition would seem to be resolved before you could apply an increased enrichment to higher burnups or to higher power levels than current higher burnups.

Now I'm pretty sure you all are aware of this but in the presentation there was a suggestion that the dispersal could only occur under certain conditions and that if those conditions weren't present then you wouldn't have to, wouldn't have to worry about dispersal.

I want to point out that the conditions for dispersal fuel through a balloon opening are present in very low burnup fuel.

This is seen many years ago in the work done at the Karlsruhe in Germany.

Much more recently in the work that you're well aware of at Studsvik.

With some moderate burnup fuel dispersal did occur upon handling of the fuel, I believed in all of the cases.

And then in the higher burnup of fuel in the Halden reactor test that the fuel dispersal was quite energetic when the burnup was high enough to produce a lot of fission gas bubbles near the surface that would burst and in training material.

ADAMS Accession No. ML23319A260 So I think the conditions for dispersal are always present.

We probably have to make some engineering judgment as to how to deal with that, because there is not enough research and probably won't be.

Can't be with test reactors shut down to answer the question definitively. But I guess the final point that I want to make is that any option that you consider that involves continuing to use the current embrittlement criteria in 50.46 in my opinion is not viable because I think the petition shows clearly that the peak cladding temperature in maximum oxidation limits are not effective in demonstrating the adequacy of the emergency core cooling systems.

That's all.

Joseph Messina 1:37:18 Thanks for your comment, Ralph.

We are aware of your petition and its relationship to this increased enrichment rulemaking effort, but we also suggest, recommend that you submit a formal comment to the increase enrichment rulemaking regulatory basis.

Ralph Meyer 1:37:41 I'm not sure that actually need to be the connection.

You could change the regulation to permit higher enrichments.

The problem comes when you try and use those higher enrichments to either increase the burnup or increase the power level of current burnups around 60,000 GW days per ton.

So I'm not sure that the FFRD issue handicaps the effort that you're on to raise the burnup limits, but it certainly gets involved when you're trying to use those in increased.

I think I misspoke.

Enrichment limits. I think the problem occurs when you try and employ those increase enrichment limits to either increase the burnup of above about 60 GW days per ton or increase the power level at current burnups.

OK.

Joseph Messina 1:39:08 Thank you, Ralph.

ADAMS Accession No. ML23319A260 Ralph Meyer 1:39:10 Thank you.

Daniel King 1:39:13 Thank you.

And with that, we'll go to Al.

CSONTOS, Aladar 1:39:17 Yes.

So Al Csontos, NEI, so just a couple things, one more specific and the other one more general. For the more specific comment we listened, or I listen in to the ACRS meeting that you all had for this rulemaking and the ACRS members brought up the paper that NRC had published and I can't remember, I think it's called the NRC methodology to estimate fuel dispersal during a large break LOCA.

So I don't know who wrote it, but the question there is that, you know, how do we, you know, how do you want us to.

We heard about it.

We heard, you know your comments.

During the meeting, but we're not sure if this is part of the basis.

Should we be looking into that paper in response to some of the FRN questions?

How should we take that paper?

And since it was discussed, we just want to know how do we incorporate that or is that your position in the paper or is that more of a research activity?

Just some thoughts, just would like to clarification, that's all.

Joseph Messina 1:40:40 Thanks Al.

Yeah, that was just an activity by our Office of research by Jennie and Andy and the NUREG paper was more important for us to get a better understanding of the quantity of fuel that would be dispersed.

Just an estimate and we wanted to have this in mind as we assess the various alternatives and we thought it would be important to begin to see if we could demonstrate the, our ability to predict dispersal, if we pursue an option where we analyze the consequences of fuel dispersal.

ADAMS Accession No. ML23319A260 So we acknowledge that we showed that we can estimate it and obviously there are improvements but this is more just, this was more just an activity by our Office of Research of everything going on.

CSONTOS, Aladar 1:41:37 Yeah. And that's where we were getting it.

It seemed like the ACRS members during the meeting, they wanted to provide more emphasis on those results. And then taking that and looking at that result and impacting it on the regulatory alternatives that were discussed.

And so the question there is like, how do you, you just said that you have plans to improve those calculations right and so then it's like how do we use that result and then the future I guess results.

Making you know.

Joseph Messina 1:42:21 Yeah.

I wouldn't say there's necessarily, you know, plans.

We've had discussions on how we can improve the results, but obviously you know how much effort we put into improving those results depends on which option we pursue.

You know, we don't want to spend a ton of resources to better predict something when it's when it's not, not really necessary.

So yeah.

CSONTOS, Aladar 1:42:47 Yeah, that this is an area that we might, you know, want to have more dialogue and discussion on because it does inform those impacts.

You know the next steps, so just, that's why we asked the question.

We were just wondering how because we heard a lot about that during the ACRS meeting.

So, OK, so that was that was question number 1. Number 2 is more process question and so this is, and I don't know if this is the right time to talk about it after your presentation or if it's a larger dialogue here for all the questions, but what the industry plans to do is we are planning to answer the specific questions.

ADAMS Accession No. ML23319A260 You know in depth and provide as much basis as we can in the time period that we have to respond back.

You know, we're hoping that we get additional time to provide additional feedback on the timing and the combinations.

I think that also was talked about at the ACRS meeting was, you know, some of these different alternatives have different time frames associated with them, different research lines, different periods to completion.

And then implementation.

And also there's combinations that's a little bit of one or a little bit of three or a little bit of four and a little bit of five and it comes into a kind of a holistic path or a holistic plan that shows that it can all come together.

We understand how you've binned the comments and the questions and the requests for comments, but how do you want us to handle the holistic, you know, response that kind of gives our overall, you know, what we think would be an ideal approach.

I think that's something that you would want us to provide.

So how do we do that?

Just thoughts.

We just wanna get some ideas from you on that one.

Joseph Messina 1:44:56 Yeah, we definitely wanna hear, you know, as much as much feedback as you have.

In terms of exact process, I don't know of any project manager wanted to add anything or any management.

CSONTOS, Aladar 1:45:14 Well, let me just say that we thought that the answer to one of the general questions, I think it was question 3 alternatives, that might be a place for us to then provide an overarching kind of holistic response.

Would that be satisfactory.

I mean, one of the PM's, maybe.

I don't want to put you on the spot, Joey.

Joseph Messina 1:45:41

ADAMS Accession No. ML23319A260 Phil, do you wanna take this?

Thanks, Al.

Philip Benavides 1:45:47 Al, just make sure I'm unmuted here.

Yeah, I mean, you can provide overall anyway. I think the one thing to keep in mind, we put these questions.

Questions out there as areas of interest that, you know, they're not requirements that required answers, but they are targeted areas where it could help us.

Inform us as we move forward with the proposed rule.

Now, I don't think it has to be formed of question answer like, you know, if you want to provide this information we can go through and we can digest it however we want.

So I don't wanna be like prescriptive of you have to answer 1, 2, 3, 4, 5.

It's just wherever you feel like anyone in the public that feels like they could add value to those areas of interest would help us.

CSONTOS, Aladar 1:46:36 OK. Thanks.

Daniel King 1:46:51 Good.

Carla Roque-Cruz 1:46:51 Any other questions, comments at this time.

Daniel King 1:46:56 Seeing none in the chat, Carla.

So I think that's it, right?

Kalene Walker has her hand raised again. So Kalene.

If you wanna unmute yourself and ask your question or state your comment.

Kalene Walker 1:47:10 Yeah, the question is you mentioned the chromium cladding, are you planning to give credit to that technology.

ADAMS Accession No. ML23319A260 In your analysis, you mentioned it and I'm not sure, I missed exactly how you frame that.

Joseph Messina 1:47:31 Well, when I mentioned the chromium coated cladding I mentioned that there could be benefits.

We're not entirely sure of the exact benefits at the current moment, so.

Kalene Walker 1:47:45 Well, I would suggest you read the ATF-ISG-2020-01 because it really talks about a lot of problems that can, it acknowledges a lot of problems that can happen with that chromium coating.

So I'm not sure you can give credit for this so called ATF.

To prevent these problems that we're talking about?

Joseph Messina 1:48:11 Yes, we are.

We are aware of the ATF ISG and when we use that in any review of any chromium coated cladding submittal.

Thank you.

Daniel King 1:48:25 Thank you.

I still see no comments or questions in the chat and no additional hands raised.

So with that, it's back to Phil and Carla, thanks.

Philip Benavides 1:48:41 With that, no questions.

Let's move on to our regulatory basis summary and how to prepare and submit comments.

Next slide.

In summary, there is sufficient, the regulatory basis shows that there's sufficient basis to proceed with rulemaking for control room design criteria of 10 CFR 50.67 and GDC-19.

ADAMS Accession No. ML23319A260 Criticality accident requirements of 10 CFR 50.68 and environmental requirements of 10 CFR 51.51 and 51.52.

The regulatory basis shows, recommends no rulemaking for packaging requirements of 10 CFR 71.55 and additional stakeholder input is required prior to finalizing and recommendation for fuel fragmentation, relocation and dispersal.

Slide 54, please.

And now I'm gonna tell you how to prepare and submit comments.

Next slide, 55.

This slide shows you how to find more information on this rulemaking.

If you go to www.regulations.gov and search for docket ID NRC-2020-0034, you'll find a number of different documents including the regulatory basis document, Federal Register notices, public meeting notices and summaries, public comments and Commission papers.

You'll find more information in here as the rulemaking progresses, so check back occasionally for updates.

Slide 56, please.

This slide summarizes the instructions in the Federal Register notice and how to submit a comment on the regulatory basis. The preferred method is to go to regulations.gov, search for rulemaking docket and NRC-2020-0034, and click in the comment button next to the regulatory basis document.

Using that method will ensure that the comment goes directly to the docket with no delay.

You can also use the email address rulemaking.comments@nrc.gov or NRCs fax number or postal mail address and make sure you include the rulemaking docket number in your submission.

There's also frequently asked Questions page on commenting at regulations.gov/FAQ for your information.

Slide 57, please.

There is also commenters checklist available to you on regulations.gov with tips for effective commenting.

You can find it at the address shown here on the slide.

It will also show up on the comment submission page.

I encourage you to check it out.

Slide 58.

Now let's talk about next steps in the rulemaking process.

ADAMS Accession No. ML23319A260 I mentioned earlier that we've made the regulatory basis document publicly available and published a notice in the Federal Register requesting public comments.

The public comment period closes on November 22nd, 2023.

Once again, note that an extension request for the public comment period has been received and is under consideration.

The public will be notified if any public comment period extension by a notice in the Federal Register.

We will consider the public comments on the regulatory basis as we develop a proposed rule.

The current schedule would have the NRC staff delivering the proposed rule to the Commission in December 2024.

We would plan to have one or more public meetings during the public comment period of that proposed rule.

The public comment period would happened after Commission approval of the proposed rule, assuming they approve. After the public comment period on the proposed rule, the staff would consider the public comments on the proposed rule during the development of a final rule.

The current schedule for delivery and final rule to the Commission is June of 2026.

Note that these days may change as the rulemaking progresses.

Slide 59, please.

Here's a visual display of the current rulemaking schedule.

Once again, note that these dates may change as the rulemaking progresses.

Slide 60, please.

This slide shows you the contact information of the project leads on this rulemaking.

Feel free to reach out to us if you have any questions or have trouble finding information.

Slide 61, please.

As we do with all public meetings, we ask for your feedback and how we did in this public meeting.

You can find the link in the meeting notice at the meeting details page.

Please submit any feedback you have for us at your convenience.

Thank you in advance.

That's the end of the slides for this public meeting.

We'll now stop presenting the slides.

ADAMS Accession No. ML23319A260 Let's stop for any final questions from members of the public on this regulatory basis.

Carla or Dan.

Daniel King 1:53:32 So as a reminder, please just raise your hand on Teams or by pressing STAR 5 to do so.

So at this time, we'll see if anybody has any additional questions. And as a reminder, you can also put that in the chat.

I think we have a question from Kalene.

Please unmute yourself and state your question or comment.

Kalene Walker 1:53:57 It's a quiet crowd today, so I have a lot of questions.

So how would I proceed with learning what the spent fuel management aspects of this high burn fuel are?

There's a lack of congruency between the technical information that we know and then unresolved problems with the current spent fuel and compounding those problems with this potential new load of spent fuel.

And so fruit for questions.

Who would I ask for that and who in the NRC is looking at that, is there a division of spent fuel management?

Who were the experts on that?

Jason Piotter 1:54:42 Yes, Kalene.

I'll start with an answer for you.

Division of Fuel Management would be my recommendation for the 1st place to start with respect to the back end of the fuel cycle.

If you want to address a letter to our division director, Shana Helton.

You can correspond with her and she will distribute the questions as appropriate to the technical staff.

I believe that you have done that in the past, so you should have some experience navigating that if there are any issues that you have, you can feel free to contact me again.

ADAMS Accession No. ML23319A260 My name is Jason Piotter.

I'm a senior program manager for new fuels in the division of Fuel Management.

Kalene Walker 1:55:22 Great.

Thank you.

I'll look forward to communicating with you.

Jason Piotter 1:55:26 Thank you.

Daniel King 1:55:30 Thank you.

Are there any other additional comments or questions at this time?

So we have a question in the chat from Charles.

Can you provide any projected schedule milestones?

So I think this would be to Phil, so maybe you can go back to that slide and talk to some projected schedule milestones.

I think you're on mute, Phil.

Philip Benavides 1:55:56 Yes, thank you.

We can go back one more slide actually.

And so right here, there's a projected milestones.

Right now we're in the comment period, which as of today is the scheduled to close November 22nd.

But as I pointed out, there are, we did receive an extension request that's under consideration, so and that will be notified if that does change through the Federal Register notification.

Once we consider those, we'll develop the proposed rule and then the milestone for the proposed rule to go to the Commission as of right now is December of 2024.

You know, at that point the we will do once again another public comment period after Commission approval, public meetings will happen during that public comment period like we're doing right now for the regulatory basis.

ADAMS Accession No. ML23319A260 And so there's that.

And then going beyond that, once we send the proposed rule up to the Commission and it comes back, the current scheduled date for a final rule to go to the Commission in June of 2026. Now we do have the asterisks there that these dates are estimates at this point are subject to change and a lot of that will come down.

There's some complexities to the rule and that can affect that schedule, but right now, that is the current schedule we're working to.

Daniel King 1:57:17 Thanks, Phil.

Are there any other additional questions this time and if you need more information, feel free to put, you know, follow-up question in the chat or come off mute there.

I've got Kalene Walker has her hand raised, so Kalene feel free to meet yourself and ask her question or state your comment.

Kalene Walker 1:57:40 Thanks.

I was wondering what Ralph Meyer said that he had submitted some kind of a document to the NRC.

I was wondering if there was an ML number on that.

Philip Benavides 1:57:57 The petition for rulemaking has been received and it's still being reviewed and under consideration.

And so I don't believe that's out there yet, so.

Kalene Walker 1:58:12 It's not publicly available?

Philip Benavides 1:58:15 I don't know.

Since I don't know, I'd have to check on that.

I'm not involved with that effort so.

Cindy Bladey 1:58:23

ADAMS Accession No. ML23319A260 Yeah.

No, this is Cindy Bladey.

Yes, that's publicly available, yeah.

Philip Benavides 1:58:27 Thats publicly available?

OK.

Thank you, Cindy.

Kalene Walker 1:58:30 Is it possible to post the ML number on that if you could access it.

Cindy Bladey 1:58:34 Will do.

I'm on it.

Kalene Walker 1:58:36 Thank you.

Appreciate it.

Daniel King 1:58:36 Yes, Cindy.

We put that in the chat, please.

Kalene Walker 1:58:39 Appreciate it.

Philip Benavides 1:58:40 Alright, thank.

Thank you, Cindy.

Daniel King 1:58:43 Thanks, Kalene did you have anything else or.

OK, your hands lowered.

ADAMS Accession No. ML23319A260 So I don't see any other questions or comments in the chat and no other hands raised.

So back to you, Phil. Thanks.

Philip Benavides 1:58:57 OK.

And can we go to those last slides, please or back to where we were. With that, I'd just like to thank you for all your attendance and attention today.

Members of the public and NRC staff and management alike, and as the 2nd reminder for those who are participating by phone line, please send an email to me at Philip.benavides@nrc.gov.

That's Philip. Period. Benavides, B as in boy, E N A, V as in Victor, I, D as in David, E S at nrc.gov.

So we can include your name and business affiliation as applicable in the meeting summary.

If you participated by teams, we will have your contact information. And before we adjourn I'll ask any of our NRC managers in attendance if they would like to give some final remarks.

Joseph Donoghue 1:59:55 This is Joe Donoghue from NRR and thanks for everybody's attention to the meeting today.

And your participation and we're looking forward to the comments that you submit.

So we can do the best we can on forming the proposed rule. Thanks.

Philip Benavides 2:00:13 OK, thank you, Joe.

And with that, thank you again and we are adjourned.