CENTERS FOR DISEASE CONTROL AND PREVENTION

NATIONAL INSTITUTE FOR OCCUPATIONAL SAFETY

AND HEALTH ADVISORY BOARD ON RADIATION AND WORKER HEALTH

ROCKY FLATS PLANT (RFP) WORKING GROUP (WG) MEETING

TUESDAY, OCTOBER 4, 2022

The meeting convened at 11:00 A.M. EDT 

via video teleconference,

Dave Kotelchuck, Chair, presiding.

Vet Reporting

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2 

Members Present: 

David Kotelchuck, Member 

Paul L. Ziemer, Member 

Loretta Valerio, Member

Registered and/or Public Comment Participants:

Rashaun Roberts, Designated Federal Official

Nancy Adams, NIOSH contractor

Zaida Burgos, NIOSH contractor

Bob Barton, SC&A

Liz Brackett

Ron Buchanan

Grady Calhoun, DCAS

John Cardarelli, DCAS

Joe Fitzgerald, SC&A

Ashton Habighurst, HHS

LaVon Rutherford, DCAS

Mutty Sharfi, ORAUT OTIB

Matthew Smith

Regina
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TABLE OF CONTENTS

Centers for Disease Control and Prevention, National Institute for Occupational

Safety and Health Advisory Board on Radiation and Worker Health Rocky Flats Plant

(RFP) Working Group (WG) Meeting Tuesday, October 4, 2022......................................... 1

PROCEEDINGS .................................................................................................................................... 4

Welcome and Roll Call ................................................................................................................. 4

DCAS Overview of Rocky Flats Plant Technical Basis Documents as of January 

2021.................................................................................................................................................... 7

Occupational Medical Dose..................................................................................................... 8

Occupational Environmental Dose....................................................................................... 8

Occupational Internal Dose/Occupational External Dose ........................................... 9

SC&A Presentation: SCA-TR-2021-SP001 Review of 2019-2020 Revisions to 

Rocky Flats Technical Basis Documents .............................................................................12

WG Discussion and Path Forward..........................................................................................32
4 

PROCEEDINGS

(11:00 A.M.)

Welcome and Roll Call 

DR. ROBERTS: I've got eleven o'clock Eastern, so I'm going to 

actually open up the meeting. So good morning, everybody. Welcome to 

the Advisory Board on Radiation and Worker Health meeting of the Rocky 

Flats Plant Working Group. I'm Rashaun Roberts, and I'm the Designated 

Federal Official for Board.

The agenda, presentations, and other materials and information 

relevant to today's meeting can be found on the NIOSH website/DCAS 

website under scheduled meetings for October 2022. So with that brief 

welcome and orientation, I'll go ahead and move into our roll call. Since 

Board Members who have conflicts with regard to this site really can't sit on 

this workgroup, there are no conflicts of interest for the workgroup members 

that are here. Other staff do need to state any relevant conflicts as I move 

through the roll call. So let's go ahead and start with you, Dave.

CHAIR KOTELCHUCK: All right. I'm present. 

DR. ROBERTS: Okay. And you mentioned that Field may be joining 

late?

CHAIR KOTELCHUCK: Right.

DR. ROBERTS: Okay. And Valerio? Loretta?

MEMBER VALERIO: Uh-huh, I'm here. I was trying to unmute. I'm 

here.

CHAIR KOTELCHUCK: Okay. Welcome -- welcome, also, to this -- to 
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the working Group.

DR. ROBERTS: And, of course, Paul. 

MEMBER ZIEMER: I'm here.

DR. ROBERTS: Okay, great. So let's move on to NIOSH/ 

DCAS/ORAUT.

MR. RUTHERFORD: Okay, LaVon Rutherford -- 

MR. CALHOUN: Grady Calhoun, I'm conflicted at Fernald.

MR. RUTHERFORD: Yeah, I didn't hear Grady quickly enough, so I 

jumped in there. So this is LaVon Rutherford, I'm conflicted at Fernald.

DR. ROBERTS: Okay. Anyone else for NIOSH/DCAS/ORAUT?

MR. CARDARELLI: This is John Cardarelli. I'm conflicted at Fernald.

DR. ROBERTS: Okay.

MR. SHARFI: Mutty Sharfi. I am conflicted at Mound.

DR. ROBERTS: Anyone else NIOSH/DCAS/ORAUT? Okay, let's move 

on to SC&A.

MR. FITZGERALD: Joe Fitzgerald, no conflicts.

MR. BUCHANAN: Ron Buchanan, SC&A, conflicted at Los Alamos.

DR. ROBERTS: Anyone else from SC&A? Let's move on to HHS and 

contractors.

MS. HIBIGHURST: Ashton Habighurst, HHS, no conflicts.

MS. ADAMS: Nancy Adams, NIOSH contractor, no conflict.

MS. ROBERTS: Thank you. Anyone else for HHS or contractors? 

Okay, what about the departments, DOL, DOE? Hearing none, let's move on 

to see if there are any members of the public who would like to register their 

attendance now. Hearing none, thank you and welcome again.
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I just need to go over a couple of additional items before I give the 

floor to DR. Kotelchuck, who's, obviously, the Chair of the this workgroup. 

So in order to keep everything running smoothly and so that everyone 

speaking can be clearly understood, please, everyone, be sure to mute your 

-- your Zoom, or if you're on the telephone, to mute your phone when 

you're not speaking. The mute button for Zoom is typically in the lower lefthand corner of your screen. If you are attending via telephone, press star 

six to mute if you don't have a mute button. If you need to take yourself off 

mute, press star six again.

Again, the materials that are relevant to today's meeting can be found 

on the NIOSH/DCAS website, and all materials were sent to Board Members 

and staff prior to the meeting. So with that, I will turn the floor over to you, 

Dave.

CHAIR KOTELCHUCK: Okay, thank you. I just want to comment that 

as we begin, this is our first working group meeting since the death of Terrie 

Barrie who was an active participant in our deliberations. Terrie was a fine 

person and vigorous advocate for Rocky Flats' claimants. We will miss her. 

And, of course, all of us want -- I'm sure we want to express our 

condolences to Nancy on the recent passing of her husband. Thank you for 

being here.

Okay, let us now proceed to today's agenda. And the agenda is we 

first -- we have on the agenda the DCAS overview of the Rocky Flats Plant, 

which LaVon will get -- will present, and later, Item Two is the SC&A 

presentation that Joe and Ron worked on --developed. If I may ask for 

those -- for folks making that presentation, is this order a good one or 
7 

perhaps the SC&A folks would like to present first and DCAS later? I'm 

usually -- 

MR. RUTHERFORD: Actually, -- Dr. Kotelchuck, this is LaVon 

Rutherford. I -- I went through SC&A's presentation. I think this is a very 

good order the way you have it set up right now.

CHAIR KOTELCHUCK: Okay, good. All right. So we'll start with your 

with -- your discussion as -- as on our agenda. 

DCAS Overview of Rocky Flats Plant Technical Basis Documents as of 

January 2021

MR. RUTHERFORD: Okay. All right. Thank you. I'm going to share 

my presentation and see if I can get it in the slide-show format. All right. 

Can everybody see that?

CHAIR KOTELCHUCK: Yes.

UNIDENTIFIED SPEAKER: Yes.

MR. RUTHERFORD: All right. Basically what I'm going to do is, I'm 

going to go over the changes to the Rocky Flats Plant site profile, and then I 

will turn it over to SC&A to allow them to go through their review of that site 

profile and have discussions. I'm going to provide a summary of the major 

changes to the site profile, each of the TBD sections, and then after I get 

through with that discussion, I will provide a status of the revision of the 

Rocky Flats Plant internal co-exposure model. I'll also briefly discuss the 

external co-exposure model as well.

So I'm going to go through the summary of changes. We'll start with 

the Rocky Flats TBD, the introduction. In this TBD, there was really no 
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substantive change, other than indicating that the upper sections of the site 

profile were revised to incorporate Advisory Board comments and items 

associated with SEC-192. We also updated a -- the current SEC classes 

associated with Rocky Flats and feasibility limitations. You'll actually see a 

very common theme throughout these. If you recognize that our standard 

process is once a SEC evaluation and, you know, designation, determination 

is complete, we automatically establish a -- a -- a time to revise all the site 

profiles.

So one of the major drivers for changing these -- the TBDs was the 

completion of SEC-192 and the incorporation of the findings from that.

Okay. Now the site description. Again, there was no substantive 

change -- changes as well. Again, we updated to reflect Advisory Board 

comments and items associated with SEC-192 when -- and we updated the 

current SEC classes and feasibility limitations. All of the sections, if 

required, updated -¬the references were updated as well.

Occupational Medical Dose 

The X-ray, the medical exposure T -- TBD, again, updated to reflect 

Advisory Board comments and the current SEC classes. We also updated 

the X-ray doses based on information presented in ORAUT-OTIB-0006, rev. 

5, that required a few changes in some tables and such, and we also 

updated the references.

Occupational Environmental Dose

Our occupational environmental dose, again updated in accordance 

with comments from the Advisory Board and SEC-192. We also identified 

current SEC classes. And those of you that were on the Advisory Board work 
9 

-- workgroup would remember we looked at the -- during the SEC review, 

we looked at the FBI raid pretty closely. We developed a paper from that 

and -- to the workgroup in 2015. So we incorporated the information, some 

of the information, from that white paper into the environmental TBD.

Also, we updated the internal intakes for consistency with external 

assumptions. Basically, we then ensured the internal and external 

occupancy factors were updated to be consistent, updated on-site ambient 

values. Attachment B was deleted. This was a methodology for -- or it 

actually talked about identifying radionuclides of -- of concern. However, we 

had already discussed that in a previous section, so we thought it 

appropriate to go ahead and delete that attachment. And we also updated 

references as well in this section.

Occupational Internal Dose/Occupational External Dose

Occupational internal dose, again, as I mentioned, updated in 

accordance with Advisory Board comments in items from SEC-192, updated 

the current SEC classes and feasibility limitations. We also updated the 

annotation and attributions. There were some old annotations and 

attributions that we felt should be updated to currently standards of 

identifying specific documentation that supported those iteMS. And we also 

updated the references, updated the co-exposure study and updated data 

from OTIB-14, and we also added intake rates to -- for Super-S plutonium. 

We changed the guidance for post-1989 plutonium mixture to only assume a 

ten-year age, and then we incorporated a bunch of white papers from the 

SEC-192. We -- we had looked at potential exposures from neptunium in 

depth, possible presence of magnesium thorium alloys, exposures to tritium, 
10

exposures from the Critical Mass Lab, and the impact of the FBI ride -- raid. 

These items were added to the occupational internal dose.

The occupational external dose, again, same comment. I probably 

should just put this up front and not have to say it every dadgum time. But 

we did update the -- to -- to incorporate Advisory Board comments and 

items associated with SEC-192, updated the SEC classes. If you remember 

from SEC-192, we did add a class up to 1983. We identified the feasibility 

limitations from that, so that's the -¬one of the key items there. Updated 

references, and again, we update some attributions and annotations.

Again, we incorporated a white paper -- this was associated with a 

gamma cell cobalt irradiator. There was a white paper we put together on 

the -- the rear view of that and potential effects from any exposures that 

weren't captured. We added additional guidance on the application of a coexposure dose, dosimeter gap analysis, and an interpretation of external 

dosimetry record notations.

Now, just, you know, it's a pretty quick presentation, but I just wanted 

to -- thought it'd be a good lead-in for SC&A. I also wanted to give you a 

status of revising the Rocky Flats co-exposure. The all -- all co-exposure 

models, as everyone knows, are being updated to follow the criteria of IG006, ensure that we can meet that. Rocky Flats internal co-exposure update 

has started, however, it is being worked -- we have like three or four coexposure models going on at the same time with, you know, completion of 

INL, SRS, and a couple -- and another one. So it's being worked while we're 

working those, during downtime of those, so I don't have a really good 

completion estimate. But as we get a good completion estimate, I will 
11

update the workgroup and -- to give them a better idea of when they can 

expect that. As well, we don't have a good date for the start of the external 

co-exposure model. But again, as a -- as we start to get good dates on that, 

I will provide updates through the workgroup and try to keep them informed 

as we're going.

And that's all I had. Any questions? I think you're -- 

CHAIR KOTELCHUCK: Fine. And you said that the -- or maybe I 

should ask. What are some of the -- when you finish the co-exposure 

models, what -- you are going to go over then all of the individual claimants' 

claims that have been done in the past, and you will update them, right?

MR. RUTHERFORD: Exactly. What we do is, we will do a program 

evaluation report to determine that potential claims that could be affected by 

the updated co-exposure model, and then the claims that could be affected 

will be -- you know, we will indicate that to the Department of Labor for 

rework.

CHAIR KOTELCHUCK: Very good, very good. And -- and are there 

any responsibilities of the -- of the working group when the co-exposure 

models are completed? They will be submitted to us for a final...?

MR. RUTHERFORD: It's pretty much -- pretty much been standard 

that the workgroups have been identified, and they've been reviewing those 

or SC&A has been reviewing those co-exposure models, so I would 

anticipate you would do that as well.

CHAIR KOTELCHUCK: Okay. Good. Thanks. Are there other 

questions or comments? I'm sure there will also be when we -- when we 

hear from SC&A, and I think it'll give us a little more depth to -- to respond 
12

both to the what -- this presentation as well as SC&A. So perhaps we 

should go to SC&A right now.

MR. FITZGERALD: Yeah. Good morning. Joe Fitzgerald. Can 

everybody hear me?

CHAIR KOTELCHUCK: Yes.

SC&A Presentation: SCA-TR-2021-SP001 Review of 2019-2020 Revisions to 

Rocky Flats Technical Basis Documents

MR. FITZGERALD: Excellent. So anyway, this has quite a long history, 

and I think the reason for the amount of detail and listing in our report --

this was the one in December of this past year -- frankly, was to sort of 

bring it -- everybody up to date, provide a status as well as a review of 

those issues from 2005. I mean, they're 17 years old, so they don't get too 

much older than that.

Anyway, the way we went ahead and did the review of the TBD, we did 

go back and reviewed all the 2005 evaluations. There were 11 findings and 

four observations. So we started there as a starting point and looked at the 

most recent version of the TBD and, frankly, just did a comparison of to 

what extent the -¬these issues -- and there were a number of sub issues 

that were behind major findings and observations -¬to what extent they're 

reflected in the current version. And we also stepped back since these TBDs 

are relatively recent and reflect, I think as LaVon was saying, a lot of the 

work that the workgroup has done and NIOSH has done over the past 10 

years.

Took a -- took a broader look at the technical basis documents, the 
13

TBDs, and tried to see if there were any new issues or any new -- new 

questions that may have arisen from the revision process itself. So those 

were the two key aspects that we -- we reflected in the December '20, '21 

review.

And I'm going to go through this at a relatively high level but the --

again, the evaluation that we did, did pretty much turn over all the rocks. 

There's a lot of sub issues that we addressed in our review, and they are --

they are detailed in that report. So if any -- if there's any desire to bore 

down into any one of these issues, we certainly can do that and we'll 

probably reference that report.

And we did get a response in July to the review that we conducted. 

And -- and our assessment today reflects the status of -- of where we came 

out in terms of NIOSH's response to our December report.

Next slide please. Okay, so sort of diving in. The first TBD is the site 

description TBD, which is the, sort of, broad history of operations and the 

description of the site. And we -- we found that -- that on our previous 

issues, the ones that we identified in 2005 have been addressed in rev. 2. 

And clearly -- and I -- I say this with some comments. Rev. 2 is more 

comprehensive in the scope and depth and, you know, a lot of the earlier 

TBDs, back in the early 2000s were the first -¬you know, first version of the 

technical basis documents, and they clearly have become more 

comprehensive over time.

This TBD included more details on the post-operational phase of 

Rocky, which is the site closure and DMD. And that was one observation we 

had back in 2005 that we felt didn't really get into those details as much as 
14

it should have and -- as well as more specifics on operations, the time lines 

of those operations, and a number of issues that the workgroup got 

particularly focused on in the latter years, which included recycled uranium 

and U-233, which, as you recall, figured in one of our --in one of the Board's 

SEC considerations. And those were two of the observations that were 

included in that. So we -- we thought our observation 1 and 2 -- certainly 

we'd recommend closing those. Those are certainly addressed.

The third bullet, we did have a finding that focused on the -- on the 

site description, which is finding 8, and this was a -- a -- a consideration that 

we thought more information was needed about recycled uranium. Now, 

remember, this is 2005. And clearly, NIOSH brought much more 

information on recycled uranium. I think the workgroup certainly requested 

it. And that -- that focus is now reflected in the internal dose TBD. So it --

it -- it sort of was a -- was an original finding, which has certainly been 

treated a number of times since then. And you can find it in TBD 5.

Now, the only recommendation that came out of that, it -- it does get 

a lot of treatment in TBD 5, which satisfied indirectly our concerns in TBD 2 

that the scoping of the operations that you'd typically find in a site 

description, we -- we think some of that should be brought back into the site 

description, not just simply addressed in -- in the internal dose TBD. So 

that's kind of an editorial comment. And I think NIOSH agreed and plans to 

look at that in future revisions to sort of clean that up a little bit. So on that 

basis, we do concur with NIOSH's response, and we would certainly look to 

TBD -- the next version of a TBD 2, the site description, to perhaps include 

more of that description.
15

So any -- any questions on -- on -- on our review of TBD 2 site 

description?

Okay. Moving on to TBD 3, which is occupational medical dose. We 

did have a finding on that one where, again, we felt that it should be more --

it should have been more treatment of occupationally necessitated medical 

X-ray. And there was some discussion, but we felt there were a number of -

- of issues and questions that could bear further expansion. And -- and that 

was the basis of the finding.

And as -- as we note in our report, we went through and looked at all 

the sub issues that were the basis for finding 5, and there were a -- a large 

number, actually, that I understand from the guidelines that -- of what 

constituted occupational medical exposure, potential for other types of X-ray 

exposures, uncertainties involved with determination of -- of machine 

parameters. I mean, there's a number of issues. We went through all the 

sub issues in our review, and we -- we considered them had -- have been 

resolved in the latest revision of TBD 3, and we recommend closure on that 

basis of this finding. And there were a number of sub findings. So really, 

this one, I think, has been addressed comprehensively in the revision.

We did step back, as we did in all of these, and looked at the revision 

from the standpoint of okay, this is a new addition, are there any new 

findings based on the revision itself. And we did find some editorial issues in 

terms of when the tables in the prior TBD were updated, we found some --

some transcription errors, and we identified those, and NIOSH acknowledged 

and will, in fact, address those in future revisions. So on that basis, we 

concur with NIOSH's response, and we'll certainly review any future 
16

revisions that come out.

Next slide, please. If there's questions on -- 

CHAIR KOTELCHUCK: If I may -- 

MR. FITZGERALD: -- (indiscernible) -- 

CHAIR KOTELCHUCK: I do have one, if I may, although it's probably 

more from my learning than anything else, but I have -- I -- I mean, I went 

back and I reviewed the detail document, the -- that you -- you wrote in 

December of last year. And in the environmental dose, and I -- I don't know 

if other people have immediate access to it -- but on page 16, which I have 

of that, you have something you have a section called uses screens, grids, 

and impact of offsite medical X-rays are not considered, okay fine. And then 

you said in the first bullet, do not consider the dose impact -- the dose 

impact due to less than optimal use of technology such as using screens, 

grids, or bucky systeMS. I don't know what the bucky system is. I'm not so 

well acquainted with the X-ray technology. I'm not sure also about the use 

of screens and grids. So why don't you just clarify that for me, what -- what 

those are -- or Ron?

MR. FITZGERALD: Yeah. Ron, are you on? I think that was -- I think 

that was your section.

MR. BUCHANAN: Yeah, I -- this is Ron Buchanan. Can you -- can you 

hear me?

MR. FITZGERALD: Yes.

CHAIR KOTELCHUCK: Yes, we can.

MR. BUCHANAN: Okay. No, I don't know what I'm --right here --

offhand, I don't know what a bucky system is. The grid system is -- they 
17

used to do X-rays with a grid in front of it to get a reference point, and that 

was from the early work and those sort of things. I'd have to go back and 

read and look at specifics, but the interference that those cause with the 

different views and different X-ray machines and technology way back in '05 

or '04 when this TBD was written and we reviewed it, they did not cover 

that. However, in the revised TBD and then in OTIB-6 and those as we 

progressed through the years, they do address those issues and have ironed 

those out. And so we found that they were no longer an issue for Rocky 

Flats and in the TBD 3 -- 

CHAIR KOTELCHUCK: Oh.

MR. BUCHANAN: -- as far as assigning dose.

CHAIR KOTELCHUCK: Oh, good. Thank you. I understand -- 

MR. BUCHANAN: Right.

CHAIR KOTELCHUCK: -- because putting a grid up in front of the Xray, while it may give you a location, may interfere with the quality of the Xray itself and you're often trying -- an X-ray evaluator is trying to look for 

relatively small or -- or faint signs, so anything that would in -- would 

interfere, obviously, would be something to take into account and -- and you 

have. Okay, thank you very much. I -- the grid is quite sufficient. If you 

do find out what a bucky system is, you might just email me personally 

afterward, unless others want -- want to get it. I just want to under -- 

MEMBER ZIEMER: Dave, this Ziemer. A bucky is just a -- kind of a 

bracket that holds the grid. It holds the X-ray cassette in the grid. That --

that -- 

CHAIR KOTELCHUCK: Oh, I see.
18

MEMBER ZIEMER: -- just that assembly is called a bucky.

CHAIR KOTELCHUCK: I see. Okay, very good. Thank you. As I said 

before the meeting began, I'm so glad that you're here with us to help us 

with some of the technical aspects of this -- this evaluation. Thank you.

So that's my -- my question. And so Joe, feel free to go on.

MR. FITZGERALD: Okay. And thank you, Ron.

Going on to, essentially, TBD 4, this is the environmental dose TBD as 

-- as revised. We had one finding, finding 9, from that TBD, and it really 

concerned inadequacies in addressing the potential environmental exposure 

from the -- from the routine and ambient air releases and particularly 

resuspension of contaminated soil. So there was a number of issues that 

involved that.

And some of the sub issues, we list them on our report, you know, the 

need for perhaps better source term calculations, exposure pathways, the 

usefulness of maybe identifying a time line for the (unintelligible) operations 

and -- and particle size. So there were a number of issues that -- for default 

in the -- in the environmental dose assessment process that we felt could be 

improved from the 2005 TBD.

Now, we looked at the rev. 3 -- and that was rev. 00. So we looked 

at rev. 3 of TBD-4. And, again, we found a, you know, much more in-depth 

and comprehensive assessment provided on -- on -- on the issues that we 

identified. And we went through some detail, and, again, it's probably five 

pages worth in our report, but we felt that the justification of the basis of 

what the monitoring data was -- was applied and how it was applied was --

was -- was much more detailed and comprehensive than it was back in 
19

2005. That's a major improvement. And there's much more specific 

information and guidance about how the resuspension of soil contaminants 

contributed to the occupational environmental exposure. We felt that was a 

pretty significant gap as far as the environmental dose issue for occupational 

exposure. So we thought that needs to be addressed. And, again, we would 

recommend a closure of this finding based on pretty much the -- the 

treatment that's been provided in the rev. 3 versus where it was then we 

made that recommendation in 2005.

And I would say there's a number of sub issues that went into that 

finding, which, again, given the complexities of how you assess 

contamination and resuspension, you can imagine a number of parameters. 

And we felt that a number of those had to be addressed, and they have 

been. So that -- that's where we came out with. Any -- any question on 

finding 9? Again, we can go into some more detail, but that's kind of the 

overview on that one.

Okay. There were some other issues in the TBD revision, which we 

felt were important. We did have an observation that dealt with how the 

RATCHET air dispersion models was applied, and we felt that -- let me get 

that -- we felt that the model did not address the wake effect of buildings, 

which, you know, if you think about the way buildings are configured in a 

plant like Rocky Flats, we felt that would have some impact. And the -- the 

response, I think, that NIOSH gave us is that -- is that the wake effects of 

air movement around buildings were not -- would not be significant because, 

again, the releases from the -¬and this was the major leak point, building 

771 stack, was not going to be a big impact to the wake effect just because 
20

it was relatively high compared with the -- the buildings around it. So that 

being a big source of potential exposure just would not be affected as much 

by that.

And all other elevated sources in the model, the model that was being 

used, were treated as area sources. So and terms of the dispersion model, 

the RATCHET model, the initial dispersion was assigned based on them being 

area sources, which already accounts for the effects of the wake effect. That 

observation really was a specific focus on -- that you consider the effect of --

of --- of editing of air movement around buildings in terms of the dispersion 

model. And I thought -- we looked at the response that we received from 

NIOSH on that and how it's addressed in the TBD and felt that was 

satisfactory from our standpoint on that observation. Sort of a technical 

issue on the air dispersion model.

As LaVon mentioned, NIOSH more or less repeated its assessments 

and the exchange of views and information that the workgroup had on the 

FBI investigation, and we had a if you recall, a pretty extensive exchange 

on that issue. And so our -- our purpose in looking at how this is treated in 

the TBD, and it was treated in this particular TBD, was just to walk through 

the -- you know, the -- the issues, the exchange of comments and the 

dispositioning of the issues and just to kind of validate that this pretty much 

reflects those discussions and what we believe was the workgroup endpoint 

on that. And so, we believe, you know, it does, and therefore we certainly 

recommend closure of these particular issues.

Any -- any questions on any of that? That -- that was, again, the 

environmental TBD. And even though we're going relatively fast, I -- I'll 
21

again say that there is quite a bit of -- if you go through this December 2021 

assessment, a lot of detail, issue by issue and sub issue dispositioning that 

we did in that assessment, so these -- these resolutions are based on -- on 

the sub issues as well. There weren't any issues that we could find that 

were not addressed by the revised TBD.

Moving on to TBD-5, which is the occupational internal dose TBD, 

finding 1 was the question of NIOSH's suggested use of the urine bioassay 

MDA and in terms of the values appearing low based on our comparative 

review. And our bottom line in terms of the rev. -- revision 3, is, you know, 

there's an appendix, I think it's Appendix A, that gets into the listing of 

MDAs and is fairly detailed in terms of the basis of the urine MDA and an 

added discussion on the application of MDAs in the TBD, which is a 

significant up -- upgrade from the 2005 version, and addresses the issues 

that we recently had with the information that was provided from the MDA, 

which I think was -- was not sufficient.

There was information, but it -- it -- it just was not sufficient, so I 

think this is a major upgrade from that standpoint, particularly for plutonium 

americium where we felt that there was needed more information that.

On finding 2 -- and this was kind of a general, I don't want to say, 

catch all, but it was just sort of a reflection that there was a lack of 

treatment of a number of parameters that we felt were important, 

considerations that were important for those, and some of these I would 

focus on. They included how unmonitored workers would be treated. This is 

not simply co-exposure models but also nuclide-specific exposures such as 

neptunium, thorium, uranium, U-233. There was a number of source terms 
22

that in 2005, we found to be relatively significant but there wasn't much --

and understandably at that point in time, there wasn't much in the way of 

guidance or information on how one would address workers that may 

potentially be exposed to, for example, neptunium releases or U-233.

Now, I would also add though, that, you know, somewhat in that time 

frame, a few years after 2005, actually, probably about four or five years 

ago, the Board recommended and (indiscernible) was designated for 

neptunium, thorium, U-233 for 1952 to '83. So this TBD predated the SEC 

evaluation which led to an acknowledgment of -- of not having sufficient 

data to support post reconstruction for unmonitored workers for those 

source (indiscernible).

So in a way, you know, that -¬that's not a threat in the process. And 

as LaVon pointed out, that's acknowledged in the TBD as well. So, again, 

this was the earliest version of what we thought were issues that needed to 

be treated and they, of course, ended up being treated over the ensuing 15, 

16 years that the workgroup has been addressing with NIOSH and SC&A to 

Rocky Flats' issues.

Other considerations just to mention while we're here was the FOP 

particle size, solubility issues, you know, certainly super-solubility issues 

relative to plutonium are ones that come up on almost all the sites in terms 

of how that's gonna be addressed. The calibration of lung counting for 

Americium-241 and we -- sensitivity of the bioassays from a soluble source 

term.

So there was a number of issues that are sort of basic to internal dose 

reconstruction not -- not exclusively to Rocky but to all the sites that in 
23

2005, we felt the TBD didn't go far enough in providing details. And as we 

detailed in our response -- our -- our comments in December, this is now a 

much more comprehensive TBD. And beyond just the SEC 

acknowledgments, there's a lot more information on how unmonitored 

workers are addressed for the other (indiscernible). So it presents a fairly 

complete story, whereas before there were a lot of gaps in how the dose 

reconstructors would go about reconstructing doses for those unmonitored 

workers.

Any questions for those who -- and that's pretty fundamental findings 

but, again, ones that I think I could describe as being overtaken by almost 

15 years of review and consideration, both SEC and otherwise. So in a way, 

this is almost a reflection of the work that everyone has done on these 

issues since that time.

CHAIR KOTELCHUCK: Yeah, agreed, agreed.

MR. FITZGERALD: Okay. Now, this is, as I said earlier, in addition to 

simply looking back at 2005, we kind of stepped back from the TBDs and see 

if there was any new issues that struck us at this stage of the game, and 

this -- this is more or less an observation that is just a -- you know, tables 

have been added, tables have been updated, and we found that a table, B11, just lacked units, and we thought they were (indiscernible), but we 

thought that needed to be clarified. NIOSH agrees that that will be edited. 

And therefore we concur, and we don't really see any further issue on that.

As we went along if we did see something that was a discrepancy or 

an issue, we went ahead and wrote it down and asked NIOSH for 

clarification. A lot these were resolved in their July response, some of them 
24

are to be done in future revisions. So that's kind of how a lot of these come 

out. But nothing overly substantive. Again, an editorial comment.

Next one, please. Okay, finding 5 was really addressing the question 

of ingesting in case and a direct reference to the appropriate document that 

that guidance would be based on. And, again, we felt that the -- there 

should be more specific recommendations cited in the TBD for Rocky Flats. I 

think NIOSH's response was a clarification that -- that there was -- in terms 

of ingestion, there's a more general -- general or generic treatment that 

they provide. And it's not a site-specific one that would be repeated in every 

single TBD, and this is covered in ORAUT-OTIB-60 internal dose 

reconstruction, which was issued 2018.

Now that, obviously, wasn't available in 2005 when we made that 

finding, but at this -- at this point in time, in terms of the revision, this is 

kind of the approach that apparently NIOSH has taken that really that 

guidance is provided in there, and that they will not change TBD-5 to repeat 

that guidance. And we accept that. You know, this is the way it's done now, 

and that's fine as long as it's information that's available to the dose 

reconstructor, that -- that's what's necessary. So we recommend closure. 

That's -- that's not a gap -- certainly not a gap anymore, and the 

information is available to the dose reconstructor.

We had an observation about the wound dose model and -- and I think 

our observation is that while the approach in the TBD is claimant favorable 

for the cited organs, there seem to be -- we identified a model by Guilmatte 

and Durbin, this was a 2003 model -- and remember again, this was back in 

2005 -- that was more -- seemed to be more favorable for lymph node skin 
25

cancers. And we felt that would be more of a claimant favorable.

Now, in the revised TBD -- and this is the response that we received in 

July, was that ORAUT-OTIB-22 now references the 2003 model that we 

identified back in 2005. So it's -- covered it essentially. And that certainly 

satisfies that observation.

CHAIR KOTELCHUCK: Good.

MR. FITZGERALD: Next one. Okay. That pretty much covers all the 

internal dose TBD, and I was going to switch gears. Ron Buchanan did the 

analysis not only for the occupational medical, but the occupational external 

dose, so we're going to do a tag team here. And Ron, can you pick up from 

here?

MR. BUCHANAN: Yes. Can you hear me okay?

CHAIR KOTELCHUCK: Yes.

MR. BUCHANAN: Okay. Okay. This is Ron Buchanan with SC&A. And 

as Joe has alluded to, a lot of water's went under the bridge since 2005, and 

the TBDs was written sometimes before that. And so we've done a lot of 

OTIBs, had a lot of meetings, and I think I spent most of -- about half of my 

time for about 10 years on Rocky Flats and some of you Board members did 

too, and especially on the external -- I know it's a little simpler than some of 

Joe's issues on the internal. But we did have quite a bit of discussion on 

external, and we find that we're looking at finding 3. We'll go through these 

in findings and anything new that we might have came upon in our 

evaluation to the revised TBDs.

And we find that TBD-6, the patient external dose, these findings were 

resolved by the revised TBD, and we find that finding 3 in particular -- we'll 
26

go through this by number -- and now we also have to remember that 

sometimes we didn't have issues or observations.

We kind of just threw things out in early days before we had an 

organized system. We did have findings. So some of the findings had many 

aspects to them or follow-on issues. So Joe and I tried to go back and look 

at all those to make sure we -- we addressed them or find where they were 

addressed.

Finding 3 was particularly concerned with the interpretation of the NTA 

film data for workers that wasn't included in NDRP. Now, a lot of you might 

recall the NDRP was a very extensive program, and we went through a lot of 

back and forth on that. And we did work that out, and revision 3 of NIOSH 

does address issues for workers that may not have been included in NDRP. 

And so what is used to (indiscernible) is the neutron-to-proton ratio coupled 

with the available co-exposure data. In other words, if the neutron -- if the 

worker was unmonitored or under monitored or the problems with the 

records, you remember ND -- the NTA film had problems with lower-level 

discrimination of the energy, and so I went through that, and ultimately DOE 

sector and then NIOSH TBDs and a number of discussions on that, and they 

have worked out a system in the Rocky Flat TBD-6, revision 3 where using 

neutron-to-proton ratio if there isn't sufficient or correct data available, and 

also coupled with the co-exposure model data. And LaVon just referred to 

an upgrade of that and -- and so that is what will be used for workers that 

may not have been covered by the NDRP. And so we wrote that up in our 

2021 report after a review of revision 3 of TBD 6, and we recommend 

closure this finding. So it has been sufficiently addressed in the last 17 
27

years.

Okay. Go to finding 4. Now, that was concern with the placement of 

the dosimetry on the person and angular dependency. And so remember, 

this is, again, in the beginning, and so we were just finding out all of the 

different variables. And revision 3 of TBD-6 does address the angular 

analysis and does an analysis of angular dependency of the monitoring 

devices. We checked those resources and studies they quote and found 

them correct. And we agree with NIOSH's recommendation in revision 3 as 

far as considering the angular distribution of the monitoring devices and find 

that it is satisfactory and recommend that this finding be closed.

Now, finding 6 was concerned -- and this is one that had a whole lot of 

sub issues to it, and so we gathered those all together that were under 

finding 6 and looked at each of them. Some of them had potential 

calibration errors. We find that how the calibration (indiscernible), what 

sources was use and such has been sorted out and been reviewed, and we 

have seen that that's been reflected in revision 3. The technical difficulties 

or deficiencies and data integrity -- of course, we went through a lot of data 

for integrity issues at Rocky Flat (sic) and things that would contribute to 

omitted dose really read as missed dose, something that would not be 

assigned. And we found that both those issues and also the missed dose 

itself find on the LOD dosimeter has been addressed in the main discussions 

at Rocky Flats and the OTIBs that came out of that.

Yes, a question?

CHAIR KOTELCHUCK: Your voice was getting fussy. The 

transmissions was getting a little fussy just toward the end on this last slide.
28

DR. BUCHANAN: Okay.

CHAIR KOTELCHUCK: Did other people have trouble? If they did, 

perhaps you might be able to repeat it. I'm sure it was just a temporary 

problem.

DR. BUCHANAN: Okay. I turned it on max. Can you hear me okay 

now?

UNIDENTIFIED SPEAKER: Yes.

CHAIR KOTELCHUCK: Yes. Thank you.

DR. BUCHANAN: Okay. I'll try to talk loud then, okay. Okay. So we 

find that those issues have been resolved in TBD 6, revision 3. Table 6-1, I 

believe it is, of that -¬of our -- of the revised TBD addresses some of those 

issues, and our report in December gives detail on that. And so we 

recommend that that be closed. That was finding 6.

CHAIR KOTELCHUCK: Thank you.

DR. BUCHANAN: Okay. The next one is finding 10. That was 

concerned with the hand and wrist extremities. And, of course, since 2005, 

we've had some OTIBs come out and these were incorporated in revision 3 

of TBD-6 for extremity dose, and we reviewed those recommendations and 

the new revision and their sources. And as in our December 2021 report, 

we recommend that that has been satisfied, and we recommend closure of 

that finding, finding 10.

CHAIR KOTELCHUCK: Okay.

DR. BUCHANAN: Okay. Finding 11 was the last of the findings. We 

had -- was concerned with potentially a significant dose from industrial Xrays and neutron generators used for R&D and nondestructive work. Okay, 
29

that was before we had a good description of the site profile and what took 

place and who was monitored mainly. And we have worked through those, 

and we find that the workers that had dosimeters would have dosimetry that 

worked around those. We looked at the calibrations of those, and it would 

cover the energy range. And so we found that the dosimetry system would 

catch any of those that were present. And so we recommend closure of that 

finding.

Okay. Now, then the rest of these, they are new issues and they're 

minor issues or, as I say, editorial issues or questions or clarifications. 

Because we went through the old findings and observations, the issues, and 

then we did review the revised TBD in light of was there anything unclear or 

errors in it. And so, the first one there on this slide had to do with clarify the 

reason for this change in neutron dose multiplying factors listed in Table 6-

16 of the revision 3 compared to the old 6-14 in revision 00. The notes in 

the neutron dose multiplying factors had changed, and NIOSH's response 

was that the multiplying factors were upgraded based on the guidance of 

OTIB-55 which wasn't released till 2006 and, of course, was incorporated in 

the later revisions and wasn't available for the original TBD-6, revision 00 of 

2004. And we concur with their response and recommended closure of that 

item.

CHAIR KOTELCHUCK: So okay, now, if I may ask, you presented two 

-- on the previous slide, you presented two multiplier factors. And you're 

saying they -- and they're rather different. And it -- it was -- they were just 

simply the old ones were replaced, and -- and there -- there's one multiplier 

now based on OTIB-55?
30

DR. BUCHANAN: No, there's a number of neutron dose multiplier 

depending on the energy range and such, but it -- it changed with OTIB-55, 

and so they updated all the neutron dose multipliers in the new table.

CHAIR KOTELCHUCK: Okay, all right. So, it was a pretty -- pretty 

dramatic replacement of some of the multipliers?

DR. BUCHANAN: Yeah. It was an update, enough to make a dose -- a 

difference that I noticed, so they explained why that was done.

CHAIR KOTELCHUCK: Okay, thank you.

DR. BUCHANAN: Uh-huh. Okay. Now, the next one is the LOD values 

for the neutrons in the revised TBD. And what we found out was that there 

was -- in Table 6-18 and 6-19 of revision 3 of the new TBD, there was a 

value listed as 226 millirem for 1962 and '63. And we could not 

determine -- we was able to be determine how they arrived at all the other 

years, but we couldn't for '62 and '63, how to get 226 millirem.

And in our second bullet point there, you see NIOSH's response that 

the equation for '62 and '63 is the LOD is equal to the blank plus 1.65 times 

the square root of the blank. And if you crank that out, you see there on the 

third line, it comes out to 181 millirem, which is the correct answer, instead 

of 226 millirem. And so NIOSH will correct that LOD value in 1962 to '63 in 

Table 6-18 and 6-19 in future revisions of the TBD. And we concur with 

that, and we'll review it when the future revision is available.

Okay, the next issue was the LOD values listed in the tables for the 

beta LOD value for twenty -- 2004 and 2005 was needed. In other words, 

okay, when they revised the TBD they added in 2004 and 2005, which 

wasn't available in the original publication in revision 00. However, there 
31

was no reference of where they obtained those data LOD values. NIOSH 

responded that future revision will provide a reference for that for those two 

years. And we concur with their response, and we'll review it when the 

revision's available.

Okay. Now, we come to -- the next issue was missing or incorrect 

references for the revision in TBD-6, and this is, again, a housekeeping 

documentation issue. First bullet point there we see that we found that 

reference that's used in the text was not listed in the reference section 

pages 64 to 69 so you can look them up, and these were three issues there, 

page 10, Page 11, and page 94. And also, second bullet there, the caption 

on Tables C-8 on page 93 should use the phrase uranium workers not 

plutonium workers. That was in here in the caption. And the third bullet 

there we see that NIOSH indicates that future revisions will correct these 

references and include them and fix the caption on Table C -- C-8. And so 

we concur with that, and we'll review it when it becomes available.

So that is a summary of our findings and resolutions and any new 

documentation issues we had. And so what we find in summary is that --

that the revised TBDs that dry -- addressed most but not necessarily all. We 

still had a few follow ups. But most of our findings of our 2005 observations 

and findings in original TBD review, we find that SC&A addressed the other 

open issues in our report of 2021 in their July of 2022 response. And we 

noted that some of those we recommend for closure, and we concur with 

NIOSH's response on the remaining issues that will remain in abeyance, I 

guess, until further revised TBDs when they become available. We'll 

evaluate that and make sure that they are incorporated in it correctly.
32

So that concludes my presentation. Any questions for Joe or myself?

WG Discussion and Path Forward

CHAIR KOTELCHUCK: Questions folks?

MEMBER VALERIO: Dave, this is Loretta. I have a question.

CHAIR KOTELCHUCK: Yes.

MEMBER VALERIO: Can you hear me?

CHAIR KOTELCHUCK: Yes.

MEMBER VALERIO: If you go back to page 10, please. 

MR. FITZGERALD: Okay.

MEMBER VALERIO: So, it notes at the bottom on the last bullet that 

NIOSH is (indiscernible) despite SC&A's observation. Is SC&A 

recommending closure of this?

MR. FITZGERALD: Yes. And we should have been more explicit about 

that. But, yes. The clarification that we received from NIOSH this past July, 

I think, clarified how they came out with -- how they treated that guidance. 

And that's -- that's -- that's satisfactory to us. So yes, that should be 

closed.

MEMBER VALERIO: Okay. Thank you.

MR. FITZGERALD: And I might add, you know, I think I mentioned 

that a lot of the varying significant issues that were raised by petitioners in 

the past, including the Critical Mass Lab and tritium issues, neptunium 

issues, and mag thorium, they all are addressed in what I think are a pretty 

detailed appendices, which I found very useful. It pretty much kind of 

encapsulates the issue and how the issue was dispositioned and resolved 
33

and, in some cases, closed by the workgroup. So those are included -- in 

this case, those are included in the TBD-5 internal dose assessment, but the 

-- you know, there was quite a bit of work, obviously, by the workgroup on 

those issues, and they're embodied now in the TBD. 

CHAIR KOTELCHUCK: Right, yes, I agree. We spent many, many 

years trying to deal with all the various Rocky Flats issues. And so it was 

not resolved until 2017. Even the SEC application. I recognize that -- well, 

maybe we'll -- maybe we should get into maybe there are more questions. 

Otherwise, perhaps we should just get into discussion with the -- within the 

workgroup, or -- Joe, you want to -- any further comments or anybody any 

further comments or questions?

Okay. I realized as we're going through this that since we have two 

new members in the workgroup, I don't know what opportunity you had --

and I apologize for not sending you our -- the working group 

recommendations back in the March 7, 2017, Board meeting that reviews a 

number of these issues, and I think that would clarify it. I don't know if you 

folks have had a chance to see it, and I apologize for not suggesting 

beforehand that you take a look at it. As I say at a in a March 2017 -- and I 

think that will clarify a lot of the issues on the revised -- the -- the revised 

evaluation report.

But I did -- knowing this, I did look carefully -- I reread carefully the 

December 2021 report by SC&A, which is really quite extensive. And -- and 

then, of course, basically NIOSH/DCAS really is in agreement. I mean, 

there's a -- there is a real agreement on what to do. And I certainly concur 

with what -- the presentation today. I -- I -- and feel comfortable with it. 
34

And, of course, these are our -- these are technical consultants, and they 

may come to an agreement in some difficult situations. And that's -- I 

appreciate that. So I -- 

MEMBER ZIEMER: Dave, this is -- this is Paul.

CHAIR KOTELCHUCK: Yes.

MEMBER ZIEMER: Could you repeat that reference to the workgroup 

report? What was the date on that?

CHAIR KOTELCHUCK: March 2017. And I -- I looked up -¬ it's the --

our working group report is given in that, at that meeting, March 2017. And 

that will discuss a number of the issues which -- which Joe alluded to a few 

moments ago. The -- the search for the magnesium thorium alloy, the 

handling of tritium, many, many difficult issues.

And I think that that -- if I had sent them to you earlier or suggested 

it, it would have helped in your appreciation of today's discussion, but I'll --

I'll certainly say that I tried to compensate for that, at least by going over 

things more carefully -- as carefully as I could. I spent a fair amount of time 

on it.

And I do feel comfortable with the report and -- and my feeling is that 

it's -- I -- I would certainly suggest that we accept the report. I don't have 

any changes that I wish to make in their recommendations for change.

I don't know how -- Paul, how you and Loretta feel. And by the way, 

is Bill Field -- did -- did Bill Field join us or has he joined us? I know he said 

he would try to come in late if he could. Rashaun, do you know, or does 

anyone? I -- I -- are you present, Bill?

DR. ROBERTS: I don't see him. Excuse me. I don't see him yet 
35

Dave.

CHAIR KOTELCHUCK: Yeah, okay.

DR. ROBERTS: And I haven't received any additional email.

CHAIR KOTELCHUCK: Right. Okay. He certainly emailed us in --

before the meeting that he would be late today. So -- so for the three of us, 

how -- Paul and Loretta, how would you suggest we proceed? I -- are you 

comfortable with the report even though this is both -- for both of you your 

first meeting of the working group?

MEMBER ZIEMER: Dave, I'm quite confident in SC&A's report and also 

I've looked at this or NIOSH responses, and I -- I think we're -- I'm fine in 

going ahead. And I can -- I can track that. You don't have to send me the 

March 2017 report. I believe I'll be able to go back on the NIOSH website 

for the meeting of -- that March meeting of the workgroup and find that 

report there.

MR. RUTHERFORD: DR. Ziemer, -- 

MEMBER ZIEMER: I do want to ask -- and maybe NIOSH can answer 

this. Going back to the original documents, the original TBDs as well as the 

revised, are those now with the -- with the updating of all the -- the systems 

at -- in Atlanta, are those now all on the DCAS dose reconstruction H -- HP 

workspace, or where are those now?

MR. RUTHERFORD: Yeah, Dr. Ziemer, this -- I want to answer a 

couple questions too, actually, on that. One that I want to point out, on our 

website you will find all the papers associated with the magnesium thorium 

alloy, the neptunium, the U-233, the -- all the various discussions that we 

had, you'll see white papers on that, response papers from SC&A, -- 
36

MEMBER ZIEMER: And all the previous work group meetings, right? 

MR. RUTHERFORD: Yes, yeah.

MEMBER ZIEMER: Okay, gotcha, gotcha.

MR. RUTHERFORD: As for the documents, we do have all of the -- I 

know that they're on the -- they're available in the RNE -- RNECP under our 

virtual volume. I'm not sure that they're under the Advisory Board's virtual 

volume. I will -- past revisions. I know all the new revisions are there. But 

if you wanted to look at a past revision, you know, to a historical closed 

TBD, I'm not sure if they're there or not, but I can -- 

MEMBER ZIEMER: Yeah.

MR. RUTHERFORD: -- make any of them available that you need.

MEMBER ZIEMER: Well, it's kind of a moot point at the moment 

because not all of us can get into that virtual workspace yet even though I 

have -- the smart card's been updated and I have a new -- a new CDC 

laptop, so it is capable of getting there. But the software, it hadn't -- the IT 

folks there or the help desk people are working on this. I cannot get access 

to workspace.

MR. RUTHERFORD: I know Lori was -- Lori Marion-Moss was going to 

-- 

MEMBER ZIEMER: Yeah, Lori -- and Lori's working on that and so that 

will be coming along shortly. I did check on it this morning, and I could not 

get in yet.

But I'll -- I'll get these other ones on the -- on the website, the 

previous meetings, so it's not a problem.

CHAIR KOTELCHUCK: Good. Good. And as I said, I think we -- first, 
37

if I were -- the first document I would look at was the work -- the -- the 

working group report in March -- 

MEMBER ZIEMER: I'll -- I'll look at that.

CHAIR KOTELCHUCK: That'll -- that's the first introduction and there 

are many -- an enormous amount of work was put in by LaVon and others 

and SC&A to try to resolve many, many issues and -- and then I think 

from -- from the -- from the report to the Board, your folks can work back 

and take a look at some of the white papers that -- for individual problems.

So okay, well good. Loretta, how do you feel? Are you comfortable 

with our -- with what's been presented that we could approve?

MEMBER VALERIO: So Dave, and -- and we talked about this 

yesterday. So what I did was I went back and I -- I did get into the virtual 

volumes, and there wasn't a whole terrible lot in there. It was just a couple 

of documents in there. The report you sent me yesterday, I -- for some 

reason, I didn't receive that until this morning. It didn't come through until 

this morning. So I started reading it. I haven't gotten very far. But I think 

both SC&A and NIOSH did a very -- I mean, you know, these presentations 

are extremely detailed. And I'm -- I'm good with -- with SC&A's 

recommendations to close some of these out.

I know that LaVon had mentioned something, and I didn't write down 

the slide, and I apologize, about not having an estimate on the -- is that the 

co-exposure models, LaVon? 

MR. RUTHERFORD: Yeah, that's correct. I don't have good dates for 

when we expect to have them finalized. We -- the internal co-exposure 

model is -¬are -- is being worked at this time. But again, it --we're working 
38

two or three other ones, and so I don't have a really good completion date 

for that, but it has started. And then the external, I don't have a good start 

date for it yet. So -- so yes. And I do commit to getting the workgroup 

updates on those as soon as they're available.

CHAIR KOTELCHUCK: Okay.

MEMBER VALERIO: Okay. So -- so I'm assuming, LaVon, that the 

same goes for not an estimate of a time frame for revising the TBDs?

MR. RUTHERFORD: Yeah, that's correct. You can anticipate the -- the 

-- honestly, when we complete a co exposure model, any of the TBDs that 

reference that co exposure model and would -- would require updating. So 

that would be one driver that would -¬would make the changes. Most of 

these, the changes that are required are -- are our -- our observations that 

are not real significant from a -- from a dose estimate standpoint. So but --

but anything that -- or when -- as I said, when those co-exposure models 

are updated, we will have to revise the internal code -- or the internal TBD 

and the external TBD, to reflect that. And so I would expect those changes 

to occur about the same time.

CHAIR KOTELCHUCK: Okay, good. I -- I may need maybe to say it, 

Rashaun, when I was talking with Loretta, I think the reason she didn't get 

the original December '21 report from SC&A was that I don't believe she was 

a member of the subcommittee yet. She -- and so she didn't get it in the 

normal course of events as I did.

DR. ROBERTS: Yeah.

CHAIR KOTELCHUCK: And that's why. So I sent it to her. I'm so 

sorry it didn't arrive until this morning, and I don't understand because I 
39

sent it out yesterday late in the day. But as I say, I'm glad you got it and 

you had a chance to start reading it.

And so I think we're really in agreement, the three of us, that we're 

ready to proceed and approve the reports and -- and bring the -- ending the 

update that -- that will be done on the co-exposure model. So should we --

can we take a vote on that at this point or would somebody like to propose? 

I think the Chair is not really supposed to propose.

MEMBER ZIEMER: Well, yeah, before you to do that, Dave, just a 

question here. I know that SC&A has indicated what NIOSH's responses are. 

I noticed there was a response document, too, where -- was there a plan to 

go through that, or do we need to?

CHAIR KOTELCHUCK: Oh, on the -- with Mr. Sharfi, or Mutty, who is 

here on the call. I thought it reflected the work, the DCAS -- I thought it 

was reflected in the DCAS report.

MR. FITZGERALD: Actually, Dr. Kotelchuck, the reason why I didn't --

I didn't go through it is because I went through SC&A's summary, and they 

agreed with our responses. Our responses were -- were actually identified in 

SC&A's presentation and -- and their agreement with them. So I didn't feel 

like it was necessary that I go back and redo that.

CHAIR KOTELCHUCK: Okay, then -- 

MEMBER ZIEMER: Yeah, I just wanted to make sure that NIOSH was 

comfortable that SC&A had properly reflected their -- 

UNIDENTIFIED SPEAKER: Yes.

MEMBER ZIEMER: I -- I -- I agree that they had, but I -¬I didn't want 

to be presumptuous that you -- you'd necessarily -- 
40

CHAIR KOTELCHUCK: Thank you. Thank you, that's --that's good. 

And I certainly -- we certainly reviewed. I know I reviewed, you know, the 

report that -- that -¬that the -- the brief report about the agreement with 

NIOSH. Okay, so -- 

MEMBER ZIEMER: Yeah, and I'm certainly in agreement with closing 

those items that they recommend closure on, and there's some that will 

carry forward for review, so with that -- 

CHAIR KOTELCHUCK: Okay. So I believe it's proper to say that we're 

all in agreement for approval of this report of the change in the -- 

MEMBER VALERIO: Yes.

CHAIR KOTELCHUCK: -- evaluation, but good. Okay. So, I think that 

closes our responsibility then, our meeting, for today, unless Rashaun or 

anyone else has any -- I don't think there's another meeting to be scheduled 

until we hear about the co-exposures.

DR. ROBERTS: Sure. Dave, just one question for you and whether or 

not you would want an item on the agenda for our December Board meeting 

for -- to update the -- the broader Board on this or -- or what you thought 

about that?

CHAIR KOTELCHUCK: Sure, sure. I -- I -- I think by all means, we --

we should be able to report back on that.

DR. ROBERTS: Okay.

CHAIR KOTELCHUCK: However, not in the detail that it was presented 

today.

DR. ROBERTS: Right, right.

CHAIR KOTELCHUCK: But a summary of that, and so it would be brief 
41

but important, and also they -- they recognize that the committee is back in 

action. We have new members, and well, it's important for the rest of the 

Board to know who they are and -- and how we're proceeding. Sure.

DR. ROBERTS: Excellent. Other than that, I don't have anything 

additional.

CHAIR KOTELCHUCK: Okay. I must say I've been looking at Florida 

and thinking about the December Board meeting. I don't envy your search 

for an appropriate place for us to get together in person. But I assume we'll 

talk about that in our conference calls. 

DR. ROBERTS: Right.

CHAIR KOTELCHUCK: Yeah. So sorry about what's happening down 

there. Okay, well, then, folks, I think for the meeting -- we're ready to 

adjourn the meeting. So thank you all for being here. And thank you all for 

your contributions. And, of course, thank you for NIOSH and SC&A. We're

dealing with some very difficult issues, very technical and involved issues, 

and doing a thorough job, as you did when we were trying to decide on the 

SEC application as well.

So with that, folks, please, for those of us who are on the east coast or 

Midwest, have a good lunch. And whoever is on the west coast, have a good 

late breakfast. Okay, bye-bye, folks.

(Whereupon, the meeting was adjourned at 12:23 p.m. EDT).