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has been reviewed for concerns under the Privacy Act (5 U.S.C. § 552a) and personally identifiable 

information has been redacted as necessary. The transcript, however, has not been reviewed and 

certified by the Chair of the Worker Outreach Work Group for accuracy at this time. The reader 

should be cautioned that this transcript is for information only and is subject to change.

NEAL R. GROSS

COURT REPORTERS AND TRANSCRIBERS 

1716 14TH ST. NW, STE. 200 

(202) 234-4433 WASHINGTON, D.C. 20009-4309 https://www.nealrgross.com 

US Department of Health and Human Services

Centers for Disease Control

National Institute for Occupational Safety and 

Health

Advisory Board on Radiation and Worker Health

Oak Ridge National Laboratory (X-10) Work Group

Wednesday, June 30, 2021

The Work Group convened via Video Teleconference, 

at 10:30 a.m. EDT, Gen Roessler, Chair, presiding.
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has been reviewed for concerns under the Privacy Act (5 U.S.C. § 552a) and personally identifiable 

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2 

Present: 

Gen Roessler, Chair

Josie Beach, Member

Bill Field, Member

Loretta Valerio, Member

Also Present: 

Rashaun Roberts, Designated Federal Official

Nancy Adams, NIOSH Contractor

Bob Barton, SC&A

Ron Buchanan, SC&A

Grady Calhoun, DCAS

Nancy Chalmers, ORAU Team

Joe Fitzgerald, SC&A

Rose Gogliotti, SC&A

Joe Guido, ORAU Team

Lara Hughes, DCAS

Tom Labone, ORAU Team

Pat Mccloskey, ORAU Team

Jenny Naylor, HHS OGC

Chuck Nelson, ORAU Team

Lavon Rutherford, DCAS

Tim Taulbee, DCAS

Keith Varnado, ORAU Team

Diane Whitten
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has been reviewed for concerns under the Privacy Act (5 U.S.C. § 552a) and personally identifiable 

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should be cautioned that this transcript is for information only and is subject to change.

3 

Contents

US Department of Health and Human Services 

Centers for Disease Control National Institute for 

Occupational Safety and Health Advisory Board on 

Radiation and Worker Health Oak Ridge National 

Laboratory (X-10) Work Group Wednesday, June 

30, 2021 1

Welcome and Roll Call/Introductions 4

Overview of ORNL (X-10) Efforts 6

NIOSH/ORAU RPRT-90 (March 2018): 

Monitoring Feasibility Evaluation for Exotic 

Radionuclides Produced by the Oak Ridge 

National Laboratory Isotopes Division 11

Adjourn 97
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4 

Proceedings

(10:30 a.m.) 

Welcome and Roll Call/Introductions

Dr. Roberts: So, good morning and welcome, 

everyone. I'm Rashaun Roberts and I'm the 

Designated Federal Official for the Advisory Board on 

Radiation and Worker Health, and this is a meeting 

of the Oak Ridge National Laboratory (X-10) Working 

Group. 

We do have a meeting agenda for today as per usual. 

If you have not seen the agenda, you can find it on 

the NIOSH website under scheduled meetings for 

today's date, along with all of the meeting materials 

and background materials, which were disseminated 

to the Work Group and posted on the NIOSH website 

in advance. 

I do want to note, if you are looking at the agenda, 

that there are four items listed on it, but it really 

should only contain three items. Item 3 is a place for 

petitioner comments, but please note that there is 

not an active petition for this site at this time. 

So I want to officially welcome all of you to the video 

conference, and first off, let's go ahead and address 

that issue of conflict of interest, and I will speak to 

that with regard to the members of the Board who sit 

on this Work Group, and in order for them to serve 

on the Working Group they can't have any conflicts 

of interest. 

So with that, let me move into roll call for members 

of the Board on the Working Group, starting with the 

Chair, Gen Roessler.

(Roll call.)
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5 

Dr. Roberts: Before we officially move into the 

meeting, I just wanted to cover a couple of brief 

items. 

So, if you are participating by phone, you need to, of 

course, make sure that you're on mute on your phone 

unless you need to speak. If you don't have the mute 

button, press *6 to mute. If you need to take yourself 

off, press *6 again. If you're participating by Zoom, 

you want to make sure that your mute button is 

engaged. You can find it on the lower left-hand side 

of your screen if you're not speaking. And I just want 

to ask people to periodically check your phone or 

computer to make sure that you're remaining on 

mute if you're not speaking. 

As I mentioned earlier, the agenda for the meeting 

can be found on the NIOSH website. Access to the 

materials were provided to the Board Members and 

staff prior to the meeting. The agenda presentations, 

background documents that are relevant to today can 

be found on the NIOSH DCAS website. 

So, with that, let's go ahead and get started. And I'll 

turn the meeting over at this point to the Working 

Group Chair, Gen. 

Chair Roessler: Thank you, Rashaun. And welcome, 

everybody. This is actually the first meeting of the 

ORNL X-10 Work Group. The members of the group 

are myself as Chair, Josie Beach, Bill Field, and 

Loretta Valerio. 

And even though this is the first meeting, this 

material will sound familiar to most of us. In the first 

place, some of us, maybe two or three of the Work 

Group Members, were Members of the Board in 2012 

when SEC-189 was approved by the Board. And at 

that meeting we had a very nice introduction by Tim 

Taulbee of the ORNL X-10 Site. 
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6 

And then, secondly, three of us on this Work Group 

are also on the Y-12 Work Group, and there's, as we 

know, an often lot of overlap there. So a lot of this 

will seem familiar. 

This is a complex site, and it's a complex situation; 

at least I find it that with the overlap with Y-12, and 

I'm sure people are going to guide us through that. 

But, to begin, we thought we'd start with an overview 

of the site. And we asked Dr. Lara Hughes, who's the 

NIOSH lead for this site, to present that. 

So, if there aren't any questions or anything, Lara, 

it's all yours.

(Pause.)

Overview of ORNL (X-10) Efforts

Dr. Hughes: I'm sorry, I was on mute. Thank you, 

Dr. Roessler. I started sharing my screen. Can 

everybody see this? 

Member Beach: Yes, I sure can.

Dr. Hughes: Okay. This is actually a PDF file, but this 

is -- since the DCAS ORAU RPRT-90 was published, 

in 2018, there hasn't really been any product of 

NIOSH, other than responses to the SC&A review that 

was presented to the Board. So, today I'm just going 

to reuse my presentation that I gave to the Board in 

April of 2018 in Oak Ridge. And I'm just going to 

present the part of this that addresses RPRT-90 just 

to give everybody an overview, because it's been 

three years and everybody might need a bit of a 

refresher. 

So, this is the Oak Ridge facilities update. And I want 

to start at slide 8. This is an overview of what was 

done for SEC-189. That was an SEC petition, and a 

Class was added up until 1955. 
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7 

During this petition evaluation, there was a section 

that was reserved in the Evaluation Report, and that 

was to look at what we call the exotic radionuclides. 

This was anything that wasn't plutonium, uranium, 

thorium, and fission products. This was the stuff that 

ORNL produced for, like, commercial and government 

applications. They produced various radionuclides in 

the reactors, or in the cyclotrons or calutrons, at Y12, and separated those out for use in various 

applications. 

So, this reserved period since the Class was added 

until 1955, this effort was not really addressed under 

SEC anymore. It was the period after the SEC period 

for ORNL, up until 1988 when the majority of the 

radioisotope production had ceased. So this was the 

period that was evaluated for this report.

Again, I'm not going to go into detail here. The ORNL 

history, a lot of it -- or some of it involved around the 

graphite reactor at the site. And that was also a 

reactor used to produce some of these isotopes that 

we're talking about here. 

This is a photograph of the site. I'm not sure from 

when; it's relatively modern. 

This is a slide I'd like to go over a little bit more. So, 

this gray, black and white schematic here is a cutout 

of, like, a schematic map of the ORNL facility map. 

And this area here is what's called the isotope circle. 

This is a collection of around ten buildings that were 

used to separate radioisotopes that were produced 

either in the graphite reactor or the Y-12 

cyclotron/calutron. 

So, again, here is a schematic that shows the 

production of the radioisotopes that took place at X10, ORNL, or Y-12, followed by a separation either at 

the ORNL labs or the Y-12 labs, and then the use was 
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8 

either on-site or off-site. So, right now, what we're 

looking at is kind of like this area where the chemical 

separations took place after the isotopes were 

produced. 

Again, some of these materials were produced in the 

calutrons at Y-12. After the calutrons initially were 

used for uranium enrichment, they were later 

repurposed for other isotope production. This is a 

picture of the beta calutron at Y-12. 

So, the goal of RPRT-90 was to assess if there's any 

glaring infeasibilities with regards to dose 

reconstruction from those exotic radionuclides. 

So, to do this, we looked at the available ORNL 

bioassay data for the period from 1955 to 1988. And 

so we have access to the ORNL database, which has 

about 100,000 bioassay results in it, starting in 1949. 

But 95,000 results apply to this period 1955 through 

1988. 

In this collection, there is an analyte code, so the 

different analytes that were assessed are coded with 

a number. And so the triple zero is what we're looking 

at. This indicates a non-standard method; so that's 

like the exotic radionuclide material.

We know from this database that it's incomplete, but 

it's not inaccurate. So, we have not collected all of 

the data that's available. We know there's some 

gross beta data missing from 1955 to 1959, but that 

doesn't really cause too much of a problem to do this 

review. 

So, we also compared the available bioassay to the 

NOCTS, the bioassay that was available on NOCTS, 

about 20,000 results, and we did a comparison. So, 

we found that NOCTS data is a little more complete 

than the ORNL bioassay database, which was kind of 

what we expected because we knew it wasn't 
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9 

complete. There wasn't any issue with accuracy, 

though. 

The in vivo data that's available for ORNL, that 

started in June 1960 with the start of personnel 

counting at the in vivo counter. This program ramped 

up to -- ended up with routine operations starting 

around 1963 and increasing from there.

So, they had a system capacity of about 100 persons 

per month to count. And the selection who was to be 

counted using the in vivo counter was based on the 

decision of the area health physicist. There was kind 

of a five-part criterion, but, you know, depending on 

what the person was working with and what they 

potentially exposed to. They did baseline termination 

quarterly and semi-annual counts. 

So, after we looked at the bioassay data, we also 

looked at the radioisotopes. What was there? What 

was the radioisotope inventory? And that data was 

parsed out of the available documentation that we 

have using shipping/sales reports, operational 

technical reports, logbooks, everything that was in 

the SRDB. So, this was quite a significant effort to do 

this. 

And at this point I'd like to, you know, point out that 

this was all done by our contractor staff, ORAU. They 

did a very thorough job finding all these 

radionuclides.

So, this list does not include service irradiations. 

Service irradiations are if an entity from a different 

site brought their material to ORNL to have it 

irradiated for some application. And that was not 

included because that would have not have been 

processed on-site. It would only have been 

considered if, like, we ended up with something like 

target rupture and there would have been a dispersal 
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10 

of material. 

So, as a result of this analysis, we ended up with a 

table, Table 6-3 in RPRT-90, that lists 213 isotopes. 

So this table starts with hydrogen, ends with 

fermium. It shows the radionuclide and the years 

during which this radionuclide was present at the 

site. 

And then, to assess whether or not there might be an 

infeasibility, we compared the annual production 

history of those 213 nuclides to the available 

bioassay methods for each year. We considered 

characteristic radionuclides emissions, such as type 

and energy, and the sensitivity of the analytical 

method. We did not reconcile quantity of radionuclide 

with the frequency of the monitoring method. 

And we determined that once an adequate method 

was indicated that this method would also be 

available in the following years, if that kind of makes 

sense. And a gap is defined as if there's no 

monitoring results present for the years of interest. 

And so we --

(Audio interference.)

Dr. Roberts: So, excuse me, Lara.

Dr. Hughes: Yeah, sorry.

Dr. Roberts: I can see that there's a phone ending in 

744 that is not muted and I think it's causing some 

interference. Thank you.

Dr. Hughes: Okay.

Dr. Roberts: I also see a phone now highlighted, 576, 

ending in 576, that may not be muted, either. So if 

you could please mute? Thank you.
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11 

(Pause.)

Dr. Hughes: Thank you, Rashaun. Are we good to go?

Dr. Roberts: I think so.

Dr. Hughes: Okay. Thank you. So, the main product 

of this analysis is this table that's presented in RPRT90, of which you see an excerpt here on this slide. 

NIOSH/ORAU RPRT-90 (March 2018): Monitoring 

Feasibility Evaluation for Exotic Radionuclides 

Produced by the Oak Ridge National Laboratory 

Isotopes Division

And so, for each radionuclide, we list the bioassay 

method code that was found. And then at the top, 

this is the years, this is the section that starts in 

1955. And then for each field, we did a color or an 

indicator. So, green, G, means that for this year, 

1955, for technetium-99, the radionuclide was 

present at the site, there was a bioassay method 

available that could be used to identify this 

radionuclide, and that we do have sample results in 

the bioassay database. 

N means the radionuclide wasn't present and there's 

also no samples -- that no radionuclides were present 

in that year, so we did not identify any samples, 

either. 

Yellow means the radionuclide was present. A 

bioassay method was present, but we did not have 

any samples during that year. 

And red means the radionuclide was present, but 

there was no method identified to detect 

radionuclides, and that we needed to do some further 

analysis to see what's going on with this radionuclide. 

So, we identified 34 radionuclides that needed 
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12 

additional research. Six of those are iodine 

radionuclides, for which we suggested a dose 

reconstruction method in Appendix C. Twenty eight 

of these have very short half-lives, less than one 

year, and decay was either electron capture or 

isomeric transition. 

So, for these, we came up with a kind of source-termbased approach to assess what doses could be 

incurred from these radionuclides where we don't 

have a method. So we did the listed inventory for 

each of these radionuclides and estimated an intake 

of 1 times 10 to the minus-5 of that listed inventory, 

and calculated 50-year committed organ doses to the 

highest organ from these. And we determined that a 

dosimetrically significant intake was not likely. 

This is the table. It's also in the report. So, these are 

doses in millirem. These are fairly small. I think the 

highest we're looking at is this one, it looks like 1.4 

rems to the lung, which is probably in the first year 

of exposure. So this is not an extremely high dose.

And, moving on, we did a little special assessment of 

the iodine exposure potential. Iodine was produced 

for commercial application since 1946 at ORNL. Since 

1958, this was done through separation from reactor 

fuel. And the production from 1946 through 1964 

ranged from 1.3 to 3,600 curies per year. 

We have limited personnel monitoring data during 

that time. There's thyroid monitoring that took place 

from 1944 to 1954. There was also workplace 

controls available. And the separation buildings were

3026D and 3028, but the exposure really was 

possible wherever reactor fuel was produced. And 

they also started whole body counting for iodine in 

1961. 

So, what happened is we looked at the data from 
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13

1944 through 1957 -- actually, 1943 through 1957. 

We looked at all available data that was available for 

iodine, and we separated out into chronic and acute 

intakes. And we took the chronic data that was 

available and fitted it to a log-normal distribution, 

derived a 95th percentile intake from this data, and 

came up with the 5.4 times 10 to the 5 picocuries per 

day intake. This is represented here by this black line. 

So these blue squares here, diamonds, are acute 

intakes that were present during that time. As you 

can see, the issue is that we're having a little gap 

here where we don't have a lot of iodine monitoring 

data. But there's some acute data here, there's some 

acute data here. 

So, what we suggested is that the chronic 95th 

percentile of this intake derived from 1943 to 1957 

bounds the acute intakes in the post-1955 period, 

right here. And so we determined that this was 

appropriate to assign to unmonitored workers from 

1955 to the onset of the whole body counting for 

iodine in the early '60s.

So, this really wraps up the RPRT-90 recap. So, this 

RPRT-90, this was published in March of 2018 and it 

was presented to the Board in April, and then we 

received an SC&A review of RPRT-90 in October of 

2018. And there were seven findings and six 

observations. 

In June of 2020, NIOSH issued a response to this 

SC&A review, and then SC&A provided a review of 

the NIOSH response to the SC&A review of RPRT-90. 

So we have quite a number of reports now. And this 

latest SC&A report came out in January 2021. 

So this is where we're at with ORNL and RPRT-90. So 

I think this concludes my introduction and summary 

and recap, so if you have any questions, I'd be happy 
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14 

to take them.

Chair Roessler: Does anyone have any questions of 

Lara?

Member Beach: Yeah, Gen, this is Josie. I have a 

couple of questions, but I guess I'm looking for 

something overall, Lara, and maybe Tim. This kind of 

reads like an Evaluation Report, and I know the one 

that is out, what, 182 or 189, went through '55. 

Do you not have claimants for this time period, the 

'55 to '88? And I guess I'm wondering why we're 

doing a 90 report instead of an ER?

Dr. Taulbee: Well, we don't have a petition. The 

petitioner originally filed only up through, I believe it 

was 1954, and we extended the petition up through 

'56 where we found the original infeasibility. And so 

we don't have a petitioner for that latter time period. 

And what we do in these scenarios, when we identify 

an issue of concern, such as exotic radionuclides, 

what we do is we'll evaluate it, and if we find an 

infeasibility, then we'll go through the 83.14 process, 

and we'll identify a petitioner, or a potential 

petitioner, and contact them that we're having 

difficulty with the dose reconstruction, and then they 

can file under the 83.14 process, and we move 

forward that way.

Member Beach: Okay. And then I have a question for 

Lara. On page 18 of your slide presentation, the 

coding, you'll have some radionuclides in a particular 

year, and then none in the next year, and then you'll 

see them again in the next year. 

I guess I'm a little confused. Does that radionuclide 

just go away between, say, '66, then you don't see it 

in '67, but you see it again in '68? So --
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15 

Dr. Hughes: Yeah, I mean, that's possible. I mean, 

we go by inventory of information found in, like, 

logbooks and shipping records and sales records. So 

it's possible that they produced a certain radionuclide 

for -- you know, maybe they had a request, and then 

they produced it and sold it, and then they did not 

produce it the next year. At least that's my 

understanding of the process.

Member Beach: Okay, so the presumption would be 

that it wouldn't be available at all? There would be -

- okay, anyway, that's fine.

Dr. Hughes: As far as we know. I mean, it's -- 

Dr. Taulbee: Right, and that's possible for many of 

these radionuclides because they have such short 

half-lives. And so there'd be campaigns to make 

them, they would sell the product, and then, you 

know, basically any residuals decayed away 

completely. And then the following year, or two years 

later, they'd make it again. That type of scenario.

Member Beach: Got you. Okay, thank you.

Chair Roessler: Okay, are there any other questions?

Member Field: Yes, Lara, this is Bill. I was just 

curious. If you can remember, where'd that data 

came from for iodine from '57?

Dr. Hughes: '57?

Member Field: I think there is some -- '57, you said 

there weren't any programs to monitor for iodine at 

that time.

Dr. Hughes: Well, there's a few. I think -- 

Member Field: Yeah.

Dr. Hughes: Yeah, there's a few acute.
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16 

Member Field: Oh, okay.

Dr. Hughes: So, I would have to look at my 

spreadsheet. There were a few acute measurements. 

So, this would come from thyroid measurements. 

Member Field: Was there some sort of accident or 

something in post-'65 that's --

Dr. Hughes: Oh, '65? 

Member Field: The potassium iodide was 

administered in, what's that --

Dr. Hughes: Yeah, this was based on an incident 

report. A lot of the acute data that comes out of 

incident reports.

Member Field: Okay. 

Chair Roessler: Any other questions or comments? 

(No audible response.)

Chair Roessler: Well, then I just have one comment. 

For the rest of the meeting today, there are obviously 

a lot of situations at ORNL and the related site, Y-12, 

but we're going to concentrate just on RPRT-90, on 

the exotic radionuclides. And it's my understanding 

from the agenda that we're going to -- and maybe 

I'm wrong -- but have four presentations. 

First, NIOSH is going to present on RPRT-90. Then 

SC&A is going to talk about their review of RPRT-90. 

Then we'll hear NIOSH's response to the SC&A 

review. And then, finally, the fourth report will be 

SC&A's response to NIOSH's response to SC&A's 

review.

So it seems to me that the Work Group really doesn't 

have to make any determinations or conclusions until 

we get down to the final report, which will be by
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17 

SC&A. And maybe NIOSH will respond to that.

Am I right on that, Rashaun and Tim?

Dr. Hughes: Gen, this is Lara. We don't have another 

presentation. We will respond to the issues in SC&A's 

presentation. I mean, that would just be based on 

the discussion in the Work Group, but there's not 

another presentation.

Chair Roessler: Okay. So, on the agenda, then, for 

Item Number 2, the presentation, we're not going to 

have the first presentations, we're going to go right 

into the iii. Is that correct?

Dr. Taulbee: Gen, this is Tim. The way SC&A has 

really laid out their presentation is that Lara just gave 

the review of RPRT-90, an overview of it. And then 

SC&A, the way they've laid out their presentation, is 

going through each of the findings, and they discuss 

their finding and then NIOSH's response, and then 

their response. So, really, your Items 2 and 3 are 

combined into that next presentation. 

Does that make sense to you? 

Chair Roessler: That makes sense. That's the way I 

thought it should be. I just wanted to make sure. 

Then we'll be ready to jump right into SC&A's 

presentation, which is the January 2021 report. 

Member Beach: Gen, I wanted to point out, under 

Section 2 on the agenda, the first under i, that report 

shows it's in October 2019, and that should be '18, I 

believe. I looked for an October –- 

Chair Roessler: Right. Yeah. That was corrected in 

one of the emails we just got the other day.

Member Beach: It was? Okay. So I have an older one, 

then. Okay, thanks, sorry.
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Chair Roessler: That's right, though. Okay, then. I 

think we're ready for the SC&A's report.

Mr. Fitzgerald: Yeah, thank you, Gen. This is Joe 

Fitzgerald. And Bob Barton, I think, is going to put 

the presentation up.- 

Mr. Barton: Yeah, Joe, that right. Lara, I'm going to 

need you to stop sharing so that I can take over the 

screen, because it won't let me while your slides up, 

okay?

Dr. Hughes: Okay.

Mr. Fitzgerald: And just while you're doing that, Tim 

is correct. Given the back and forth, we thought it 

would be much more coherent for the Work Group if 

we presented our original findings and cited NIOSH's 

response to that finding. And, of course, NIOSH can 

jump in as we go through this if there's anything to 

add. And then, you know, pretty much our reaction 

to that. You know, it's been a couple years, obviously, 

since the 90 was tasked. We were tasked in April 

2018. Actually, it's three years. So, there's been 

some fruitful, I think, exchanges on this in the 

meantime; clarifications, if you may. So I think, you 

know, again, time was well-spent, but I think this is 

an opportunity to catch the Work Group up on pretty 

much, you know, what was in that exchange. So we'll 

go through this that way. 

Bob, if you can go to Finding 1? The intro was pretty 

much covered by Lara in terms of RPRT-90 and, you 

know, some of the exchanges. So, really, we ought 

to just go ahead and start with Finding 1. 

And Finding 1, you know, again, RPRT-90 certainly 

was a bit of a different type of report from a number 

of ones that we have looked at. And so we had some 

questions on scoping, because, obviously, the isotope 

production was the central part of the review, but, as 
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with many sites, the D&D and waste management, 

some of the other handling aspects of radiological 

materials, we were looking for some clarification as 

to how this review was scoped. So, on this particular 

one, we asked for the scoping in terms of whether it 

would include D&D and waste management. And 

NIOSH responded that the scope of RPRT-90 was 

purposely limited to the production phase in terms of 

both the Oak Ridge and the Y-12 footprints. And it 

was not intended to be an evaluation of whether a 

co-exposure model type approach could be 

developed for every single nuclide. 

So that was the response. Again, I thought that 

clarified our question, again, regarding, you know, 

where this began and left off. And so we accept that, 

and understand that it is specifically the production 

phase and does not address other phases, including 

D&D, construction, maintenance, and all the other 

issues. 

Now, I would footnote that recommendation for 

closure by saying that, of course, if there's any 

infeasibilities, then that could have implications for 

these other phases. I mean, obviously, if the 

monitoring was not feasible, then certainly that 

question might carry over to D&D and waste 

management, as well as other activities, like 

maintenance. 

But in the context of production, we're satisfied with 

that answer. Finding 2. 

Chair Roessler: Joe?

Mr. Fitzgerald: Yeah? 

Chair Roessler: Can I interrupt a minute? I'm 

wondering if this would go more easily and smoothly 

if we discussed each finding as you went. And I think, 

in a case where there's a recommendation, then the 
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Work Group should have a vote.

Mr. Fitzgerald: Okay. Well, fine. I'll turn it over to the 

Work Group, then.

Chair Roessler: Okay. So on Finding 1, then, SC&A 

recommends closure. Are there any questions or 

comments from Work Group Members on that?

Member Beach: I guess for me, just when you talk 

about excluding the D&D and that maintenance 

group activities, where does that get picked up at? 

Because this is such a different scenario than we 

normally deal with. I just want a little clarification on 

that.

Dr. Taulbee: This is Tim. I'll jump in, if you don't 

mind, Lara. 

Where that would be picked up is in like a coexposure model, is where that would be picked up. 

The scope of this report was to evaluate what 

radionuclides were produced, and which time 

periods, and was there bioassay or a monitoring 

method associated with them? That's the full scope 

of this particular report. 

What you're asking about, you know, which workers 

are monitored and were they monitored, would all be 

covered under a co-exposure model development.

Mr. Fitzgerald: And if I can add, Josie, this is Joe 

Fitzgerald. That was my sort of footnote comment a 

minute ago, that, you know, assuming that, you 

know, the feasibility analysis as presented RPRT-90 

is accepted by the Work Group as-is, there would be 

no reason or basis for a co-exposure model 

consideration. 

So, you know, that's kind of the basis for the 

recommendation, but it does have that asterisk. Of 
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21 

course, when we get to Finding 3, we do raise some 

questions about how that all works, you know, this 

question of capability versus feasibility.

Member Beach: Okay, thanks.

Chair Roessler: Okay, any other questions, 

comments? 

(No audible response.)

Chair Roessler: Then I move that the Work Group 

accept SC&A's recommendation for closure on

Finding 1. And I guess the Work Group Members can 

just respond.

Member Field: This is Bill. I agree.

Member Beach: Yeah, this is Josie. I'll agree with that 

also.

Member Valerio: This is Loretta. I agree as well.

Chair Roessler: Okay, thank you. So, go ahead, Joe, 

then on Finding 2.

Mr. Fitzgerald: Okay. Finding 2, you know, it's a 

pretty extensive listing, and I'll certainly give credit 

to ORAU for the work that they did putting this 

together, but we did go through and just do a bit of 

a cursory validation of the listing, looked at some of 

the source terms that were in the SRDB as applying 

to the buildings and facilities that were radioisotopehandling facilities. And we identified some 

discrepancies, mostly just to clarify how that relates 

to how the document was put together. And NIOSH's 

response was that the discrepancies that we did cite 

were related to the scope of the document, but the 

isotopes reduced by the isotopes group certainly is 

different than a more general analysis of the overall 

nuclide inventory at Oak Ridge. 
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So, if one were to, again, confine the scope of 90 to 

production per se and not look at everything that was 

in these facilities, which would be representative of a 

broader Oak Ridge National Lab inventory, then you 

would have a somewhat more constrained list. And, 

again, we wanted to understand the scoping for 

RPRT-90 since, again, I think that's also important 

for the Work Group in terms of what we're actually 

considering. 

And I think in this last bullet NIOSH made it clear that 

the inventory listing itself was developed 

independent of a broader facility listing, which is what 

we were looking at, and therefore would be different 

from that list. 

So, that clarifies the question of the nuclide scoping, 

and, again, we accept that and recommend closures 

to the Work Group on that. 

Chair Roessler: Okay. Any questions on Finding 2?

(No audible response.)

Chair Roessler: If there are none, then I move that 

the Work Group close Finding 2. Work Group 

Members?

Member Beach: Gen, this is Josie, I'll accept that 

closure. 

Member Field: This is Bill. Agreed.

Chair Roessler: Loretta?

Member Valerio: Sorry, I was trying to unmute. I 

agree.

Chair Roessler: Okay. Good. Then we can move on to 

Finding 3.

Mr. Fitzgerald: Okay. Well, obviously, Finding 3 is 
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probably a bit of the meat of our concern over the 

approach in RPRT-90, 

And, again, RPRT-90 is a bit of a unique animal. I 

mean, it certainly is a good effort to scope out the 

nuclides for a particular production operation. But, as 

we wade into the waters of looking at capability and 

feasibility, both of which are terms used in RPRT-90, 

obviously, as the Work Group knows, and as we've 

done in the Board, feasibility is a loaded term. And 

we're concerned about the context by which 

feasibility's being used in RPRT-90. 

Anyway, our finding basically is Attachment A, which 

is the lengthy listing of in vitro bioassay methods as 

a measure of capability lacks information about how 

those methods were actually applied, or whether 

they were even applied, for the nuclides in question.

And in our report we raised questions about how, 

certainly for other sites in terms of reviews, in terms 

of bioassay procedures, the actual practice, what was 

done at the site, didn't necessarily marry up to what 

the procedures called for, or even what the 

technological capabilities provided for. And we 

offered up some examples. 

Most pointedly, I think we cited Los Alamos as an 

example, an illustrative example. Obviously, we don't 

try to compare SECs, but I think the precedent is 

there, where a technological capability in terms of in 

vivo monitoring of mixed activation products was 

claimed as a basis for the feasibility of monitoring for 

MAPs. And it turns out that, in that particular case, 

even though that even though the capability existed 

for some years, it was not applied routinely to looking 

at MAPs at Los Alamos in a way which would have 

provided a reliable basis for dose reconstruction, and 

was certainly a basis for the SEC for a time period at 

Los Alamos.
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24

So, just one example, but there's other examples at 

other sites where the procedures for bioassays and 

other dosimetry techniques were available at the site, 

but were, in fact, not applied in practice. And that's 

our concern, in that regard, that, in terms of RPRT90, there is an equating of capability which comes 

down to an existing procedure and technology with 

actual practice, which is the feasibility of monitoring 

that particular nuclide, and therefore being able to 

dose reconstruct against that nuclide.

And even though, I think as Tim was saying, that, 

you know, this is a survey to look at nuclide-bynuclide feasibility to ascertain whether an evaluation 

review, Evaluation Report, would be necessary, this 

in effect becomes a de facto evaluation because 

you're looking at the monitoring for these exotics and 

establishing whether the capability construes 

feasibility of dose reconstruction. That's what's 

basically stated as an intent. And it becomes a de 

facto evaluation, which would preclude a full-fledged 

evaluation review, an ER, which would go further and 

establish whether the weight of evidence would 

support dose reconstruction. 

So we're concerned about, you know, what seems to 

be a de facto evaluation, that has some of the 

elements of full-fledged evaluation but does not look 

at the weight of evidence, which would include 

implementation, would include whether in fact the 

procedures were applied consistently, would look at 

whether or not the monitoring for the years in 

question could be validated or not.

So, that part, that's the essence of Finding 3. Now, 

the NIOSH response is that NIOSH intended RPRT-90 

to be a review of the isotopes handled by the isotopes 

production group in comparison to the available 

bioassay capability. Okay? And though not all 

available data on sporadically produced radionuclides 
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25

will be of sufficient quantity to allow for their use in a 

co-exposure model, this alone is not indicative that a 

potential exposure could not be bound with sufficient 

accuracy. 

And, again, our response was a review of dosimetry 

capability, while necessary to validate that 

measurement techniques were technically acceptable 

and available -- which I think RPRT-90 accomplishes 

-- is not sufficient to address the feasibility of dose 

reconstruction, which is the intent that was listed in 

RPRT-90. 

And our point is identifying the number of samples 

devoid of exposure potential considerations over the 

30 years of isotope division production we do not 

believe satisfies the co-exposure guidelines, even 

though this is not a co-exposure review. Certainly, a 

presentation that there were samples taken -- in 

some cases, missing samples -- without at least tying 

that to what the potential for exposure to that 

particular source term is, we don't think satisfies this 

question of data adequacy.

So, again, we get back to the conundrum of what 

RPRT-90 actually means. You know, is it an 

evaluation of feasibility of dose reconstruction? 

Because it basically lists that as one of the purposes. 

Or is it a comparison of capabilities for the isotopes 

produced, which is the response that NIOSH has 

provided to this finding. 

It can't be both, in the sense that if, in fact, it is a 

feasibility review for dose reconstructability, that is 

almost one and the same with what an ER examines, 

and goes beyond the simple comparison of 

capabilities. Essentially, it equates the capability in 

terms of the paper analysis, the procedures, the 

technology, with the feasibility of dose 

reconstruction, which gets into whether or not you 
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26 

can establish an exposure potential and whether the 

monitoring on-site actually took place. Did it actually 

take place? 

At other sites, the reality did not match the paper, 

and that's the concern that we are expressing.

Chair Roessler: Okay, I assume NIOSH is going to 

respond to that. Or are there questions from the 

Work Group? Either can go next.

Dr. Taulbee: If I could interject here, I want to clarify 

a few things that Joe stated that caused me a lot of 

concern. 

In no way does RPRT-90 preclude an Evaluation 

Report. It was never intended to be that, from that 

standpoint. This was an evaluation, as I indicated, of 

a comparison of what was produced and whether 

there's a bioassay method that was available. 

What we are looking for, at the beginning of this, was 

there any gross infeasibilities that could exist that we 

do need to move forward with an SEC evaluation 

from that standpoint? And we did that, actually, 

coming out of this report. Plutonium-241 is one of 

them that was produced at Y-12 that came out of this 

report that ended up resulting in a recommendation 

here.

This is kind of a screening method, if you will. So, 

there's feasibility of different degrees. Okay? This is 

also never intended to be a co-exposure model, full 

evaluation, that SC&A seems to be wanting us to do 

all in one report here. That was not the intent of this 

particular report, neither was it to be a final 

evaluation. 

When we go through and we do a co-exposure model 

and we find that maybe one of these radionuclides, 

we go through, and we find that we don't have 
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27 

enough bioassay in order to do a co-exposure model 

for that particular radionuclide, then we can go down 

the 83.14 path and designate an SEC from that 

standpoint. 

So, to, you know, flat-out say that we haven't proved 

all of these things, we know that with this report. This 

report was to be an initial evaluation of what 

radionuclides were produced at which time and which 

bioassays available.

In an Evaluation Report, bioassay is only one of the 

keys for whether we can do dose reconstruction. 

There's workplace monitoring that goes on, air 

sampling data, contamination surveys, as well as 

source term data that can be used to estimate doses. 

I just wanted to make those clarifications before we 

go forward.

Mr. Fitzgerald: And before the Work Group examines 

this, Tim, on page 6, bullet 4, which gets into the 

purposes of RPRT-90 -- and this is what gave us real 

pause, and I'll quote -- this is one of the purposes: 

evaluation of identified monitoring gaps to determine 

if dose reconstruction for these exotic radionuclides 

is feasible, period.

I hear what you're saying, but that's not really what 

this says. I mean, this is very deliberate and very 

specific, the fact that this will determine if 

reconstruction for these exotic nuclides is feasible. 

So, yes, I can see where this could be a bridge to a 

screening process, but this review will conclude 

whether or not dose reconstruction is feasible. So I 

think this goes further than what you're alluding to, 

based on what actually is stated in the report.

Dr. Taulbee: And if I could follow up to that?
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Chair Roessler: What page were you on? Were --

Mr. Fitzgerald: Page 6, bullet 4 of RPRT-90.

Chair Roessler: Oh, RPRT-90, okay. Go ahead, Tim.

Dr. Taulbee: And if you look at the date of when 

RPRT-90 was approved, and if you look at when IG6 was approved for methods for co-exposure models, 

things have changed. Okay? 

Back in 2018, we had a draft Implementation Guide 

that had not been approved by the Board yet. We 

now have an Implementation Guide approved by the 

Board. We now know the criteria that we have to 

evaluate. And this report was written before that, 

okay? So, we now know the criteria that we have to 

grade against in order to do that, in order to meet 

these things. 

So, while it might have been the initial intent to be 

that, from a feasibility standpoint, now that we have 

IG-6 out and approved, we know what the criteria are 

that we have to meet. This report didn't meet that. 

We know that. That's why we would do a co-exposure 

model that would meet all of those criteria in IG-6. 

Member Beach: And this is Josie. I'm just going to 

make a comment. I feel like what you're saying, Tim, 

really makes this a difficult issue for the Work Group 

when we're comparing something to an earlier report 

that you say basically needs updated, and we're 

supposed to make a determination on a report that 

is outdated at this point.

And there's a lot of questions that SC&A has posed to 

NIOSH in their final report --well, in all their reports. 

The one I'm specifically talking about is January 8, 

2021. There's several questions that need to be 

answered by NIOSH. And so this creates a difficult 

situation, I believe. 
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Dr. Taulbee: Right. If I could interject a little bit of 

kind of our plan here along those lines. 

Whether you want to leave this finding open or closed 

is entirely up to the Work Group, you know. 

Obviously, it is. But what I'm trying to make the case 

for is that the types of things that SC&A is asking for 

in Finding 3 and in Finding 4 are -- well, Finding 3, 

mostly -- are really things that would be addressed 

in a co-exposure evaluation or OTIB. This isn't 

something that we would revise RPRT-90 to 

incorporate. And that's what I'm trying to get at from 

this particular comment. 

We know these things have to be addressed, 

especially for a co-exposure model, and we plan to 

do so. We know that RPRT-90 needs to be revised 

based upon, you know, some of our response to 

SC&A findings. We've agreed to incorporate some of 

the things that they've said. But this particular 

finding of wanting us to go through and basically do 

a full co-exposure evaluation within RPRT-90 is not 

the intent of RPRT-90. That would be a separate OTIB 

that would be done. And from that standpoint, SC&A 

is, obviously, free and would be welcomed, and the 

Board to review that and provide comments, and 

hopefully we wouldn't see this comment again 

because we would address it in the OTIB for the ORNL 

co-exposure model.

Does that make sense, Josie?

Member Beach: It does, Tim, but it's also a huge 

issue, so, yeah. Thanks. 

Chair Roessler: So, to me, it seems like Tim has 

answered the concern here. However, I think before 

the Work Group would accept it, we have to have a 

mechanism for making sure this is in writing, that we 

have something to go back on and follow. 
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Member Beach: Yeah, I agree with that. I'm in no 

way ready to close this item.

Dr. Taulbee: May I suggest, then, that you leave it 

open pending the development of an ORNL coexposure model? 

Chair Roessler: Leave open until development of an 

ORNL exposure model. Okay. How does the Work 

Group feel about that?

Member Field: Hey, Tim, this is Bill. You also said you 

were going to update RPRT-90. Is that right? I mean, 

if you clarify the intent, I think that takes care a lot 

of the concerns.

Dr. Taulbee: That's correct.

Member Beach: And this is Josie. Can I ask when the 

plan to update 90 is, when it's on your work scope?

(Pause.)

Dr. Hughes: I think, Tim, you're on mute.

Member Field: You're on mute. Yeah.

Dr. Taulbee: Sorry. The update was pending the 

outcome of this Work Group meeting, in large part to 

get feedback from the Work Group. So, I mean, if 

we're in agreement with these, you know, some of 

the things that SC&A reported to close out, and the 

Work Group agrees with this type of response, then 

we will do the update. 

So, I can't give you an exact timeframe. I'm sorry, 

Josie, but it would be on our list to do next with this. 

Chair Roessler: So, Joe, if NIOSH says that they will 

develop an ORNL exposure model and they will 

update RPRT-90 with regard to these comments, 

would you be willing to close this finding?
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Mr. Fitzgerald: Well, you know, I think what we said 

earlier was we can keep it open pending the delivery 

of these products in the future. 

Our only concern is that RPRT-0090 has been issued, 

and clearly it's been overtaken by events, as Tim was 

suggesting, and what it basically states is not what 

it's intended to provide, which is a firm finding on 

feasibility. So, that's a pretty important change, so I 

would recommend to the Work Group to consider 

keeping it open, but I'm quite comfortable with what 

Tim is suggesting, which is, you know, to look at a 

co-exposure model and to come up with a revision to 

RPRT-90 which would emphasize it's a comparison of 

capability which is fine as a screening tool, but not go 

so far as to establish feasibility which is what the coexposure work would do. So, I think that would be 

the resolution. 

Chair Roessler: So then I guess I make the motion 

that the Work Group accepts SC&A's 

recommendation that this item remain open, pending 

the development of an ORNL exposure model, and an 

update of RPRT-0090. Does that include everything? 

Member Field: This is Bill, I think you've covered it.

Chair Roessler: Okay. Then, so I guess Bill accepts.

Member Beach: This is Josie. I'll accept that also, 

Gen. Thanks.

Member Valerio: This is Loretta. I agree. 

Chair Roessler: Okay, thank you. Then I think we can 

move on to Finding 4.

Mr. Fitzgerald: Okay. It's going to be Ron or Bob. I 

can't remember which one.

Dr. Buchanan: Yeah. This is Ron Buchanan with 
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32 

SC&A, and Finding 4 I'll discuss now. 

Now, Finding 4 was concerned with the feasibility of 

monitoring the 28 radionuclides considered not 

adequately addressed. 

And this centers around Table 7-6 of the original 

RPRT-90. So can we have the next slide, Bob? 

Okay, the red blocks in Table 7-2 and 7-3 mean that 

the specific radionuclide was present in inventory in 

a specified year, but additional analysis is necessary 

to determine if a nuclide represented an infeasibility 

from a monitoring perspective.

Now, Table 7-6 on page 41, RPRT-90, uses the 

derived air concentrations from Table 7-5 to illustrate 

the maximum organ dose for a hypothetical intake.

Next slide, please.

Now, SC&A expressed concern about the results of 

this table and what it meant to feasibility of a dose 

reconstruction, and we understand NIOSH's response 

was that implementation of the monitoring program 

is indicated by the availability of bioassay cards 

showing results for the respective method. And any 

available bioassay data would be used to assign dose 

to claimant. 

And additional review of available records and 

monitoring procedures will be ongoing using the data 

available in the Site Research Database. 

And next slide.

Okay, gaps in the table. Table 7-6 in the original 

RPRT-90, there were some gaps where there was 

missing data, and in NIOSH's 2020 response, they 

presented some supplementary information to 

address some of the gaps in Table 7-6 in the original 
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33 

RPRT-90, and we evaluated those additional 

information, and we agree that they was correct, but 

we feel that the doses in Table 7-6, although they're 

not alarming, they don't appear insignificant for 

potential unmonitored exposure. 

For example, you know, we report on the IREP tables 

anything one millirem and greater, and all these were 

greater than one millirem. 

And so, we don't feel that just presenting the derived 

dose maximum maybe an organ would get from 

exposure to this, does not correctly address the 

problem of assigning dose to someone who had 

intake if they were monitored for some radionuclides, 

a whole body counter, a urinalysis, or whatever, and 

they were assigned a dose for certain radionuclides. 

If these radionuclides weren't being monitored for, 

and apparently there wasn't a method at time to 

monitor for them, then we don't feel that addresses 

the monitoring feasibility question.

Next. And so in this slide, we say that we don't feel 

that the nuclide represents an infeasibility from a 

monitoring perspective. We feel that remains 

relevant. 

And that is not that it should be addressed more 

completely, and we don't feel it was completely 

addressed in Section 7.2 or Section 8 of the original 

report or NIOSH's recent response. 

So, where it leaves SC&A as saying, okay, the 28 

radionuclides was considered to need further 

analysis, and the only analysis it really received was 

to calculate the maximum hypothetical dose to an 

organ that it might receive from a certain exposure 

to them, so we don't know if it answered your 

question that was originally posed, and can we 

monitor for these or are the bioassay records there? 
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34 

So that's why we recommend it remains open, and I 

don't know if NIOSH has plans to further address 

these in any updates, or have done any further work 

on these or not. I'll let them respond to that.

Chair Roessler: Okay, yeah, Tim probably wants -- or 

Lara might want to respond first on this? 

Dr. Hughes: Oh, I can. Is Tim here? If he wants to 

chime in.

Dr. Taulbee: No, go ahead, Lara.

Dr. Hughes: No, I mean, one thing I'd like to remark 

on, bioassay is not the only, you know, the only 

means that we can use to do dose reconstruction, so 

this is based on a source term, basically. 

So this is like a bounding source term approach, kind 

of, application, so this is kind of what we're 

suggesting for these radionuclides for which there is 

no bioassay method available, and there has not 

been any additional work on this since this was 

published, so this is kind of what we're suggesting. 

And Tim, if you'd like to add.

Dr. Taulbee: Sure. The part that I would add is, what 

exactly is SC&A, the Work Group, looking for for us 

to demonstrate the feasibility for these radionuclides 

for which we do not have bioassay? 

So these would not appear in a co-exposure model, 

it would be an exposure model, either from source 

term or from air sampling data, or contamination 

surveys, along those lines. 

What we presented to you was a source term-based 

type of model that Lara and her team developed of 

taking the inventory that was produced and assuming 

a fraction of it was inhaled, and what is the resulting 
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35 

doses? And Lara presented that back in her 

presentation earlier, and you see these 50 year 

committed doses are very low. 

You know, as SC&A said, they're not alarming, but 

they're not insignificant. Well, we agree they're not 

insignificant, they're more than one millirem. 

What we're proposing is to assign an exposure 

model, this source term exposure model, that would 

then be used for dose reconstruction for these 

radionuclides. 

And again, you know, these 50-year doses are rather 

low when you look at it, and it's mostly due to the 

type of radiation emission. 

Many of these are electron capture decay 

mechanisms for these radionuclides, which don't 

deliver very much internal dose at all.

Member Beach: So, Tim, this is Josie, or Lara. Has 

that exposure model been developed as yet? 

Dr. Taulbee: It is proposed. They're in RPRT-90. That 

Table 7-6 --

Member Beach: Okay, and so --

Dr. Taulbee: -- goes through what it is we proposed. 

Member Beach: So that is the proposal?

Dr. Taulbee: Correct.

Member Beach: And there's no other work that you 

intend to do for that exposure model?

Dr. Taulbee: Well, if the, you know, Work Group 

doesn't like that exposure model, or, you know, 

wants us to do further work, we certainly can. 
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36 

We have not looked at air sampling data, we have 

not looked at other, you know, mechanisms. We 

simply looked at the source term method.

Chair Roessler: So what I'm hearing you say, Tim, is 

that, in the cases where you don't have the bioassay, 

you're going to depend on using the source term as 

a bounding way of estimating dose, and that seems 

really consistent with everything that you do and 

have done. 

I don't really understand SC&A's comments or why 

that's not suitable.

Dr. Buchanan: Okay, this is Ron again. Well, because 

in RPRT-90, it just presents the maximum dose. It 

doesn't say when this will be applied and to whom 

it'd be applied. How do we know who's going to be 

exposed? 

Would you apply this to everyone all the time, or, you 

know, how would you know that this was going to be 

applied and when, to who?

Dr. Taulbee: So, if I'm understanding correctly, 

SC&A's question then is really more of who this would 

be applied to, and from an implementation type of 

standpoint, not that those doses don't represent a 

bounding dose. 

Is that correct, sir?

Dr. Buchanan: Well, assuming that we accept this, 

because it really wasn't proposed as a co-exposure 

model or it wasn't stated in RPRT-90 when it would 

be used. 

It just says, okay, here's the facts, here's the list of 

doses. But there is no further explanation of how or 

when it'd be used. So, say that we were to accept it 

as being bounding, when would it be used, to what 
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37 

workers, because you had many years, and you had 

a lot of different workers. 

Sometimes the stuff was here, sometimes it wasn't. 

Just like you said earlier, there was periods of use, 

periods of non-use. 

So, it's just kind of to me hanging there in the air, 

okay, this is a map from dose for these radionuclides, 

but how would you actually use that?

Mr. Barton: And this is Bob. 

I think a lot of this goes back to really what has been 

clarified as a more limited scope of what RPRT-90 

was intended to accomplish, whereas we read the 

words, you know, feasibility of dose reconstruction, 

which, as Joe mentioned, is a very loaded word in this 

program.

We took that to mean that this was essentially laying 

out dose reconstruction methods, and in some cases, 

it did explicitly do that, such as for radioiodine, which 

we're about to get next. 

But I think the clarifications that were made today, 

that, listen, this report was issued back in 2018, I 

believe a year before the actual IG-006 was actually 

put into action officially. 

So I think there's a little bit of confusion, and again, 

our original review was also in 2018, so we were 

operating sort of on the draft IG-006 IG-006 

guidelines, which don't -- as you pointed out, Tim --

don't necessarily apply here because they hadn't 

been approved yet officially, and so that's going to be 

further down the line, is some of these methods, such 

as the source term method that was sort of outlined 

but not explicitly laid out, as Ron pointed out, as to 

who's going to get what doses, from what areas, and 

how do you identify workers?
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38 

All these sorts of things that usually go into the 

overall feasibility discussion really probably aren't 

applicable here, even though the word feasibility was 

used.

So I think that's where the confusion lies in a lot of 

these findings, which again date back to before IG006 was finalized as well. 

So I think, Tim, partly we do agree with you there 

that, listen, a lot of these questions are about, can it 

be implemented in a feasible way such that dose 

reconstruction overall is feasible for all these different 

radionuclides? 

And as has been made clear today, that was not the 

intent and scope of RPRT-90, which appears to be, 

possibly with the exception of radioiodine, limited to 

a comparison of what we know about the source 

terms of the site and what we know about the 

bioasssay capability at the site, and that seems to be 

a scope of RPRT-90, and a lot of these other 

questions remain relevant but weren't intended to 

necessarily be answered by RPRT-90, but will be 

answered down the line, at least that's my 

understanding of the discussion so far on this. 

Member Beach: Well, and this is Josie. I have a 

question then for you, Bob and/or Ron. 

Based on what Tim has discussed earlier today, has 

that changed your recommendation for Finding 4, or 

do you still believe it should remain open? 

I believe this is a little bit connected to Finding 3 also. 

But anyway, have you changed your 

recommendation?

Mr. Barton: Well I guess, in my opinion, it's very 

similar to Finding 3 in that it's a relevant question 

going forward, whether or not we want to close it 
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39 

under RPRT-90 review and await the forthcoming of 

a co-exposure model, which I assume would cover all 

of these different exposure sources.

It would essentially be commuted to any future 

reviews of the co-exposure, depending on how that 

comes out from NIOSH's research and evaluation of 

co-exposure feasibility.

So in a sense, this is possibly not entirely relevant to 

RPRT-90 specifically, but certainly relevant to the X10 discussion going forward. 

So whether or not we want to keep it open so that 

we're keeping this in mind when co-exposure 

modeling is being discussed, when that happens in 

the future, and certainly the overall question I don't 

think is going away, but possibly under the guise of 

RPRT-90, it could go away. 

Ron, I think I talked over you there a little bit, if you 

want to weigh-in.

Dr. Buchanan: Yeah. This is Ron again. Well, the 

problem I had when I did the original evaluation of 

RPRT-90 was on page 43. I was left with the 

impression, in the summary, the last sentence there, 

it says that these relatively low radiotoxicity of these, 

some isotopes in comparison with a bounding 

potential intake, Table 7-6 lends credence to the 

decision that a significant intake of one of these 

nuclides would not be credible.

So, to me, significant intake means that -- well, it 

told me that you weren't going to consider it further. 

Significant intake, that it wouldn't be dosesignificant. 

So, that is why I felt that Table 7-6 just left the reader 

hanging in the air what are you going to do with it? 
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40 

Okay, these are the doses, what are you going to do 

with it? 

And even if RPRT-90 isn't a co-exposure model 

paper, it really left me the impression that it was just 

going to be disregarded.

And now you're saying that's not true, but I think the 

wording on page 43 could be improved to not give 

that impression.

Chair Roessler: So it seems then what we should do 

here to be consistent with Finding 3 -- and let me 

know if I'm wrong in this approach -- but it seems 

that SC&A wants to recommend that this finding 

remain open until NIOSH updates RPRT-90, and then 

some wording in there, some short wording that will 

identify exactly what you're looking for?

Member Beach: Gen, yeah, that's what I was thinking 

also. This is Josie. 

I also, Gen, wanted to -- Tim mentioned other 

sampling results, air samples, things like that 

associated with this finding.

Tim, can you expand on that a little bit, of what --

Dr. Taulbee: Well, what I was meaning is that if, you 

know, if our current approach is not acceptable, I 

mean, there are other methods that we could do, but 

I mean, we feel the current method is bounding, and 

demonstrates that, you know, dose reconstruction is 

feasible using this type of approach. 

And, you know, one of the goals of all of our reports 

whenever we do an analysis of something like this, is 

that it eventually ends up in the Technical Basis 

Document for dose reconstructors, and, you know, it 

might just be a reference type of scenario.
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41 

But what we wanted to try and point out here is that 

these were radionuclides where we, you know, 

identified they produced, produced these, and there 

is no bioassay method. 

So, the only method for dose reconstruction that 

we've come up with is this, you know, source term 

type-based approach. 

And as you noted here now, these are, you know, 50-

year committed doses, so, you know, when we go to 

apply these or implement them, some of them that 

are very low, there may not be any dose to be 

assigned, you know, because, you know, if it's less 

than a millirem, you know, in a given year, we 

generally don't, you know, assign that dose. That's 

kind of the de minimis type of value.

So, but then there's others in that list. You know, 

clearly I think it's tin-119 metastable that, you know, 

would have, you know, a dose assigned from that 

standpoint. 

So, we can update the implementation that SC&A is 

asking for in RPRT-90, or we can clarify it as, you 

know, as I think you were suggesting there, Ron, of, 

you know, the feasibility statement that we, you 

know, stated that there would not be a significant 

intake.

We can change wording there, or we can, you know, 

add the additional -- well, we need to change that 

wording anyway -- but we can add the additional 

language in this one or we can give the instructions 

in a Technical Basis Document update. 

Is there any preference from the Work Group there? 

Member Field: This is Bill. I think changing the 

wording would go a long way to solving the problem. 
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42 

Dr. Taulbee: Okay. 

Member Field: Yeah.

Dr. Taulbee: We can do that.

Member Field: Tim, I did have a question, though. 

And it seems reasonable to use a source term model, 

but I'm wondering, when you have air sampling data, 

wouldn't you look at that to see if there's any red 

flags with using source term? 

Dr. Taulbee: We don't physically -- well, I don't know 

that we physically have it in the SRDB. I can't check 

right now.

Member Field: Okay. 

Dr. Taulbee: But I don't believe that we have 

captured the air sampling data in large scale. We 

know it exists.

Member Field: I see.

Member Beach: This is Josie again, sorry. 

It seems like there's a lot of information that could 

be still obtainable that NIOSH or SC&A doesn't have 

access to. Is that correct?

I mean, you haven't gone back to the facility. 

I know one of SC&A's recommendations was to do 

some more interviews, or do interviews, because I 

don't believe that's been done.

Anyway, it seems like there should be more out there 

that would help this process.

Chair Roessler: But the thing is that they often use, 

when they don't have bioassay, the source term 
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43 

approach, and then particularly in cases where it's 

very low, and before we accepted this approach as a 

bounding method, so to me, I'm satisfied.

Member Beach: No, and Gen, I agree with that, but I 

also know that there could be a lot more information 

available that is not available at this point --

Chair Roessler: But if --

Member Beach: Because it hasn't been looked for onsite.

Chair Roessler: If you don't need it to come up with 

a satisfactory estimate, then it seems like it's not 

necessary to go look for it. 

Member Beach: Oh, I'm not sure I agree with that, 

but -- and I'll leave it at that.

(Simultaneous speaking.) 

Member Field: But Tim, you said there's no bioassay 

data. Is that correct?

Dr. Taulbee: Not for these radionuclides. 

Member Field: Yes. 

Dr. Taulbee: That's correct. But -- yeah. That's 

correct. 

Chair Roessler: So to address this finding, I guess I'd 

ask SC&A, I think it's okay to leave this finding open 

and it's comparable to Finding 3, but we need some 

wording in there that says until NIOSH does -- what 

do you want to put in there to make sure that this is 

covered? 

Dr. Taulbee: I propose that until NIOSH revises 

RPRT-90. 
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44 

Chair Roessler: And would that be suitable to SC&A? 

Mr. Fitzgerald: Well -- 

Dr. Buchanan: Would it remain open until --

Mr. Fitzgerald: Sorry, Ron, please.

Dr. Buchanan: Yeah, you were saying that finding 

would remain open until NIOSH puts suitable wording 

in the revised RPRT-90? 

Chair Roessler: Okay, did somebody get that 

wording? I didn't get it written down. Does that sound

satisfactory to everybody?

Member Beach: Yes, that Finding 4 would remain 

open until RPRT-90 is revised.

Chair Roessler: Okay. I move what Josie just said, 

and we can look back to the transcript to get the 

exact wording here.

What about other Board Members? 

Member Beach: I agree with that.

Member Field: I think the concern with the wording 

has already been pointed out, so I think we know 

what needs revised. I think Tim does.

Chair Roessler: Okay. And how about --

(Simultaneous speaking.)

Member Field: So I'm all for it.

Chair Roessler: How about Loretta?

Member Valerio: I agree with that. I agree that it 

needs to remain open until it's revised. 

Chair Roessler: Okay. Then unless somebody 
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45 

objects, I think we can move on to Finding 5.

Mr. Barton: Okay. I assume everybody can hear me. 

Finding 5 is going to be a little bit different in that it 

does actually discuss explicitly assigning co-exposure 

values to a period where there was an identified gap 

by NIOSH in RPRT-90, and this is the subject of 

Appendix C for assignment of intakes of radioiodines.

So Finding 5 is related to that, as well as Observation 

6. 

So because they're sort of tied at the hip, I'd like to 

do both this finding and Observation 6 sort of as one 

issue of really the question of, how do you 

reconstruct the doses to radioiodine?

And again, this is sort of a different question than 

what we've been tackling so far because, whereas 

RPRT-90 is very limited in scope about how coexposure estimates might be developed and the 

feasibility of that, in this case, it does explicitly come 

up with a method for iodine. 

However, I'd also like before we really dive into this 

too deeply, I'd like to pose a question because it 

sounds like a lot of this, especially as it relates to coexposure modeling and IG-006, and all that, which 

post-dates RPRT-90 and our review of it, does NIOSH 

intend to reevaluate its radioiodine exposure model 

for the identified gap going forward in any future TIB 

or what have you, or is this the method that's on the 

table, and regardless of the acceptable of IG-006, the 

co-exposure modeling guidelines, it would not 

change?

Or will this change? Because I think that's really 

going to have a big effect on discussions today. 

Dr. Taulbee: It could change. Let's put it that way. 
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46 

There are some areas that we are continuing to look 

for some data that we believe exists, or potentially 

exists, and reaching out to the site, you know, from 

that standpoint. 

So, is this the, you know, absolute final? No, it's not. 

And this was proposed before as, Bob, you correctly 

pointed out, before the whole co-exposure modeling 

implementation guide was finalized. 

And so, kind of in light of that, yeah, I would say 

there would be a bit of tightening up associated with 

this, but I think it's important to go through, you 

know, what your concerns are and outline everything 

because it really kinds of puts it all on the table and 

brings everybody up to the same speed and the same 

level of knowledge here.

So I think it's important that we go through all of this 

and we hear what you have to say, and our responses 

that we've had to date about that so that we've got 

a good path forward.

Does that make sense? 

Mr. Barton: It does to me, and if it makes sense to 

the Work Group, I will continue.

Member Beach: I think that makes (audio 

interference).

Mr. Barton: Okay, I think that was an affirmative. 

Gen, I saw you pop on, and I think you might have 

stayed on mute. 

But without further ado, okay, so again, we're talking 

about radioiodine here, and it's important to 

remember that there is an SEC up through mid-1955, 

and RPRT-90 identified that there's a gap in any sort 

of personnel radioiodine monitoring essentially from 
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47 

1955 through 1962. 

And so, what RPRT-90 did is they constructed a dose 

reconstruction method for the unmonitored workers 

during that gap, and again that's '55 through '62. 

What RPRT-90 does say is a coworker -- because 

again, this is before we adopted co-exposure -- a 

coworker analysis based on thyroid monitoring 

between 1944 and 1954 could be used to assign 

internal exposure to potentially exposed individuals 

during the period from 1955 to 1962.

So again, the idea here is that you're using earlier 

data to reconstruct a gap that appears between '55 

and '62, or essentially the end of the established SEC 

period through 1962. 

That's when routine monitoring data for iodine are 

not available, and that quote can be found on page 

111 of RPRT-90. 

So just to briefly go through some of the specifics so 

you all understand sort of the components of this, the 

method that's on that table, it does use thyroid 

measurements, which is basically you take a GM 

probe and you measure how it's coming off of the 

thyroid, and there are ways to convert that to a 

thyroid burden, which then you can revert back to an 

intake of iodine using certain assumptions.

So there were about 230 thyroid measurements that 

were identified in RPRT-90. That's 230 total 

measurements among 147 identified individuals, and 

those actually span from 1945 through 1957.

Not every year in that range, but the first year in 

which NIOSH found thyroid measurements was 1945, 

and the last year was 1957. 

Just under half of those are associated with what is 
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48 

assumed as a chronic exposure to radioiodine in the 

1947 to 1949 timeframe, and the rest were evaluated 

as acute exposures, and I think this is sort of 

indicated on the slide that Dr. Hughes put up where 

they compared the 95th percentile derived intake 

rate for radioiodine, and then there were a bunch of 

blue diamonds that showed evaluated acute 

exposures in relation to that chronic intake.

And just as a clarifying question, because it did get a 

little confusing for me, I know in our original review 

that chronic exposure -- in other words, that line that 

was being proposed for unmonitored workers, again, 

during this gap period, I think it was derived from 

just the chronic exposure data from 1947 to '49, so 

not the full '45 to '57, but the co-exposure intake 

value was developed based on data from '47 to '49. 

Is that correct? Can I just verify that that is correct? 

Because that's one part of this, though it does not 

necessarily affect the entire question of how do we 

deal with radioiodine?

Dr. Hughes: Based on my understanding of how the 

calculations were done, yes, I do think that's correct, 

but if anyone from ORAU can correct me if that's 

wrong, then please do so. 

Mr. Guido: Yeah, this is Joe. That's correct. That's the 

period that we had data that we consider to be 

routine monitoring. We didn't want to use any data 

that was related to acute intakes or incidents for that

purpose, so that's kind of why the timeframe's laid 

out like that.

Mr. Barton: Okay. 

So, really what the co-exposure approach put forth 

in RPRT-90 is for the gap, which is from 1955 to 1962 

when you really don't have a lot of personal 
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49

monitoring data -- is to use a chronic intake derived 

from thyroid measurements from 1947 to 1949.

So that's an important thing to keep in mind as we 

sort of go through here. 

But the key question is for consideration by the Work 

Group -- and this Finding 5 and Observation 6, which 

we'll get to during the course of this discussion -- and 

the real question is, is it appropriate first of all to use 

the older thyroid monitoring data to forwardextrapolate to these potential exposures in the '55 to 

'62 period, first of all?

Because again, you're taking data from one earlier 

period and deriving a chronic intake and applying that 

to a later period for which you don't have that 

personal monitoring data. 

And so, a lot of these questions that we have really 

go back again to IG-006, which post-dates RPRT-90, 

post-dates the methodology put in here, and so a lot 

of these questions I think are important to put on the 

table for discussion, as Tim said, so that we're all sort 

of on the same page, and a lot of them will likely be 

or should be addressed in any future TIB addressing 

how all the exposures from these different 

radionuclides, including radioiodine, are going to be 

reconstructed.

And the things I think you really have to consider 

when you're talking about extrapolating data is what 

were the operations and conditions between the two 

periods in relation to the exposure potential?

That is, what was going on in that period where you 

have some data that you're deriving an intake value, 

versus what was happening in that later period where 

you're trying to apply that derived intake value?

And of course, this gets to a weight of evidence 
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50 

argument. 

And the Finding 5 here, again, one thing to remember 

is radioiodine, there's really two what I would call 

major sources at Oak Ridge. There's the RaLa 

program, radioactive lanthanum, which produces 

radioiodine as a byproduct because they're 

essentially taking freshly irradiated fuel and trying to 

pull off the barium and lanthanum for use in weapons 

experiments, but also they produced a lot of 

commercial iodine at Oak Ridge, and those two 

operations overlap some, and the magnitude of each 

operation, the RaLa and the commercial operations 

differed between the different time periods.

So what this Finding 5 was pointing out was that RaLa 

actually went up through 1956, so '55 and '56 are the 

first two years of that period for which we don't have 

data. 

Fifty-six was actually the last year in which they did 

the RaLa at Oak Ridge. In October of that year, they 

moved it over to Idaho and continued the production 

there.

So again, there's sort of two different source terms 

between these two eras. There's some RaLa that's 

happening in the unmonitored period, I'll call it, in '55 

and '56. 

Definitely some commercial operations during the 

entire unmonitored period, and there's RaLa 

operations happening during the monitored period, 

which he just verified is '47 to '49, as far as 

developing that co-exposure intake. 

And so I said, and again the question is, how 

appropriate is it to use this older data as a substitute 

for the period when you don't have data? 

And we think that you have to consider some of the 
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51

operations and conditions, which again may be 

outside the scope of what RPRT-90 was trying to 

accomplish.

But again it's a weight of evidence argument, but 

whether you can use this older data for later time 

periods, for the most part, a weight of evidence 

argument.

And to sort of illustrate that, I just want to show one 

portion of RPRT-90 where there was really three 

main, I call them facets, or points put forth to say, 

these are our weight of evidence of why we feel, or 

why NIOSH feels that the data in '47 to '49 would 

bound the intakes for this unmonitored period, which 

was considered '55 to '62. 

So let me just pull that up real quick, and I pulled it 

out so hopefully it will go quickly. And we'll see if I 

can -- one moment here. Okay. Yes, right here. 

So this is from Attachment C of RPRT-0090, and 

again, Attachment C was the radioiodine section. 

Let's move this out of the way. 

So you can see these numbered -- sort of numbered 

points here is that the intake value that was derived 

from '47 to '49, they put forth these three 

arguments, and really it's four arguments when you 

get to that first sentence in the bottom paragraph, 

but essentially they said, all right, let's take our 

derived intake and let's compare it to any sort of 

urinary excretion values that we see.

Now again, there's not many at all during this period 

of unmonitored exposure, and really not many more 

afterwards either, but the ones that were found and 

they compared to, they found that if you used the coexposure intake, again, derived from thyroid 

monitoring in the '47 to '49 time period, you have 

more than an order of magnitude greater projected 
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52

urinary excretion rate than what they've seen in the 

limited data that is available. 

A similar comparison was done for whole body 

counts, which was as noted in Lara's presentation, I 

think they first started making measurements in the 

whole body counter some time in I think it said '60, 

but not necessarily for iodine, and only then in a 

limited capacity in '61.

It starts to ramp up in '62, and then increases again 

past that into '63 and '64.

And we'll go through each of these because I think 

these are the important facets to look at when, again, 

we're evaluating how appropriate is it to use these 

'47 to '49 data for this latter period? 

So you have a comparison with limited available urine 

data, limited available whole body count data, and 

also this third one here, is they compared it to what 

were the air sampling limits in place at the time?

And so, if you take those intake values that were 

derived again in the late '40s, you get a projected air 

concentration that NIOSH calculated as nearly a 

factor of two greater than the operating level that 

was used at the facility during that unmonitored 

period. 

So those three are really the three main points as to 

why NIOSH believes their approach is bounding those 

potential exposures, and then again this fourth line, 

and this goes to the amount of iodine processed 

between the two periods, and this is '55 through '61 

-- I believe that should be '62 -- but they note that 

from '55, the unmonitored period, it was between 

1,000 and 3600 curie per year, whereas in the earlier 

period, you're looking at more like 9,000 to 42,000, 

so, I mean, you have almost a factor of ten increase 

in that. 
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53 

But again, we feel like there are certain issues with 

that comparison, which we'll get into each of these 

as I go through this presentation, but I think you 

want to keep these in mind as we go through, that 

these are the four I guess bases that, as I said here, 

support the application of the intake for the 

unmonitored workers in that period when limited to 

no data exists.

All right, so I'm going to pop back here to my 

presentation. And where did it go? Okay, here we go. 

Okay.

So moving along, so that first finding was really about 

the releases that we pointed out and that the 1956 

releases were reported to be close to 67,000, and the 

1947 releases -- and then again, these are the 

maximum releases based on a specific source term.

So in 1956, this is talking about the Hanford slugs 

that were being dissolved at the site for RaLa 

production. The 1947 value is a different source 

term. I believe that might be the graphite reactor. 

So we don't have these values on a year by year 

basis, we only have what was the maximum year of, 

again, stacked releases, and this is reflective of the 

RaLa operation, not the commercial operation.

I'll do the source term last. I want to get into --

because the source term goes right to Observation 6 

as well, so if we can leave that one alone for a second 

and focus on the other three, which were the 

bioassay comparison, the in vivo comparison, and the 

air concentration guideline comparison.

Okay. So if we start off with that bioassay 

comparison, so Table C-7 in RPRT-90, it gives a 

number of iodine urinalysis samples, and they're 

limited in this unmonitored period. The only years 

that have them are 1958, with two samples, 1961 
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54 

with one sample, and 1962 with five samples. 

So you really only have eight urinalysis samples 

during this unmonitored period for which to compare 

with the co-exposure assignment. 

And even in the years immediately afterwards, 1963 

and '64, you only have three samples and four 

samples. 

And I'll note that again there's two different source 

terms here, which we'll talk about later, but I think 

really what I just want to point out here is that when 

you start making these comparisons to these routine 

or the urinalysis samples that you have for iodine, 

they're very limited, so I think that needs to be taken 

into account when you're forming this weight of 

evidence argument, and should be also considered by 

the Board how much these weight of evidence 

support the proposed co-exposure model.

So they were comparing it to the highest -- that bullet 

that I showed that was in the NIOSH report -- they 

were comparing it to the highest routine sample, 

which actually occurred in 1966, November of 1966.

So the urine sample they're comparing it to is outside 

of this unmonitored period by four years, four or five 

years.

And as we'll note, this is during the year in which 

there's no RaLa anymore because RaLa ended in 

1956, not 1966, and commercial iodine also dropped 

significantly during that year, so again, you have to 

think about whether these comparisons are really 

reflective of what could've been experienced by 

workers during this unmonitored period from '55 to 

'62. 

The actual highest observed sample was not 

considered a routine sample, but was an acute 
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55 

sample, presumably in response to an incident, and 

that sample, the highest acute sample, that was in 

June of 1967 that was identified, and again that's 

outside of the period with no monitoring data, and 

that one was a factor of 130 higher than what was 

projected based on the co-exposure estimate, and 

again that was probably an acute sample. 

So again, that may be apples to oranges in a certain 

sense, but again, this is all part of weight of evidence, 

so when you start comparing it to certain urinalysis 

results, you have to consider how many do we have, 

and is that a sufficient number to be able to make a 

meaningful comparison?

So our position on this is that, you know, again, it's 

comparing one data from one period to another.

You want to establish the similar working conditions. 

Again, this is a lot of concepts that were codified in 

IG-006, and so it's not that surprising that these 

topics weren't necessarily evaluating discussion 

RPRT-90.

However, again, as we approach this with the 

discussion about feasibility -- which has been clarified 

today, and I think that's very helpful -- it appears 

that a lot of these concerns would not be captured by 

RPRT-90, should not be captured by RPRT-90 based 

on the clarified scope of the document, but are valid 

questions to ask when you're talking about coexposure, and that's exactly what RPRT-90 did for 

radioiodine, even though it was before IG-006. 

So as Tim pointed out, some of it may change, some 

of it may be tightened up based on those new 

guidelines. But again, I point out that the bioassay 

comparison is you only have eight bioassay samples 

during that unmonitored period of eight years, from 

'55 to '62.
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56 

There were comparisons made to urinalyses outside 

of that time period, but again you had no RaLa 

operations going on anymore and commercial 

operations were significantly decreased by '64, I 

believe.

But we'll see that. That's provided in a graph later on 

when we talk about source terms. 

Having said that, one thing that NIOSH provided in 

their response is, you know, what indication does 

SC&A have that if there was urinalysis data during 

that unmonitored period that you would have much 

higher values than what is established by the coexposure model?

And we obviously have to agree. If there was 

evidence of that, I mean I don't think we'd even be 

having this discussion.

Because if there was evidence the exposures were 

higher, then, you know, it would completely 

invalidate any co-exposure approach from a different 

time period.

But I think the important point there is that there's a 

significant lack of data to be able to meaningfully say 

what all those exposures were during the 

unmonitored period. 

So we don't have any evidence that they would not 

be bounded by the co-exposure approach, but that 

would really be -- again, it's proving a negative, and 

I think what we want to point out here is that the 

data itself is very sparse, so that and a lack of 

evidence is not necessarily an affirmation of different 

exposure levels. 

So that was the bioassay comparison. There's similar 

concerns with comparing it to in vivo. Again, the 

whole body count didn't appear until 1961, so the 
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57 

second to last year in this unmonitored period, and 

they really didn't ramp up the program until 1963, so 

in 1961 I believe there were about 100 in vivo 

results. 

In 1962, the next year, it was more like 400. ‘63, 

you're up over 1,000, and by '64, you're more up 

around like 1,500 a year. 

So you can see there's a ramping up period which 

spans both the last two years of what was established 

as the unmonitored period in RPRT-90, and really the 

ramping up of the in vivo program, which seemed to 

be hitting its stride by 1964, which again, the period 

that this co-exposure estimate was intended to 

assign doses to was '55 to '62. 

So again, the question is how relevant is this whole 

body count data for the period prior? 

And now again, there were a couple in '61 and '62, 

but we have nothing prior to that in the unmonitored 

period with which to make any comparisons. RaLa 

had ended in 1956, so again they're not really 

reflected of that source term.

You know, and a lot of these questions again, the in 

vivo data, we only have it in essentially summary 

form, so what do we really know is how many 

individuals measured? At least that was the 

references presented in RPRT-90. 

We know how many individuals are measured, and 

how many had a measurable radioactivity that wasn't 

associated with some of the two standard elements 

that you'll find in in vivo, which is potassium-40, K40, and caesium-137. 

And what we don't know is how many folks who 

worked with the radioiodine were included in that in 

vivo program, you know, what percent, and not only 
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58 

how many, but what percentage. And the 

documentation really only suggests that the in vivo 

program was directed for its investigations of known 

or suspected internal contamination exposures.

So there's a lot we don't know about those in vivo 

results, and as I said, they were very limited. Very 

limited for the time period that we're discussing 

because they didn't really start measuring iodine until 

1961, and then only a very limited number of people, 

then it started to ramp up from 100 in 1961 to 

basically nearly 1,500 in 1964.

So there's that ramp up period that starts in the 

unmonitored and goes into the subsequent years. 

And so again, NIOSH's response is basically, you 

know, that wasn't the point of looking at this in vivo 

data. 

The co-exposure estimates are done using the 

thyroid monitoring, and again, it's the thyroid 

monitoring from '47 to '49. And this was just for a 

comparison, again, to build a weight of evidence that 

the method proposed would be bounding compared 

to the limited data that you do have in the '60s.

So we concur in the context of that comparison 

purpose. Again, some of these comments are not 

entirely relevant to RPRT-90 anymore now that the 

scope has been clarified. But again, this is all about 

when you're extrapolating data from one period to 

the other. 

In this case, we're forward extrapolating the 

exposure data from '47 to '49, forward into '55 to '62, 

and now the comparisons are using in vivo data after 

the period, so that extrapolated through the coexposure derived thing.

So there's a lot of caution that we believe must be 

taken that I think is outlined in IG-006, so I think a 
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59 

lot of these concerns probably would be addressed in 

any future TIB, again, identifying what the coexposure method is going to be. 

And so the third one was again a comparison to the 

air concentrations, and just like in vivo, these come 

from annual HP reports that reported the total 

number of air samples per year. Not any more 

granularity than that, and there was no information 

on the location, or even the magnitude of the 

individual samples.

And in NIOSH's response, again, it's like, hey listen, 

this was just for a comparison and a weight of 

evidence comparison to our proposed co-exposure 

guidelines. 

And the comparison isn't to the actual 

measurements. We don't have those. It's just to the 

allowable operating levels. 

And what SC&A had pointed out is that based on the 

Site Profile, the operating levels indicated that we're 

actually 50 percent higher than what was projected 

from the co-exposure estimate, which NIOSH said, 

well no, actually the Site Profile is an error, and what 

it was recording as that operating level, and so that 

would have to be corrected to the lower level, which 

would then conform with the NIOSH's conclusion that 

the co-exposure model is actually two times higher 

than the operating level, as opposed to the operating 

level being 50 percent higher than the co-exposure.

Moving on. So again, our point here is that it's 

important to evaluate what the actual air 

concentration measurements were, so we may know 

how many there were in a year, but where were they?

Are they general air samples, are they breathing 

samples, are they in the iodine production years? 

What were the actual measurements in the iodine 
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60 

production years? 

Were there certain job locations where you were 

regularly, you know, close to the limit, exceeding the 

limit, and what have you? 

And we don't have that granularity right now, and 

again, that might be something that would have to 

be explored again going forward when evaluating coexposure methods against the IG-006 criteria.

But also, this notation that the original Site Profile 

was an error when SC&A pointed out that, well listen, 

your Site Profile has an air concentration that's 

actually higher than what would be projected by your 

co-exposure model, and NIOSH said, well that 

citation is actually an error, and they provided their 

reference for it, and we're going to look at that in a 

second.

We don't believe that the original Site Profile was 

actually an error, and you'll see in a moment why. 

And this comes down to whether the limit, again, for 

beta gamma, an error was one times ten to the minus 

eighth, or was it three times ten to the minus eighth? 

And I think that's going to be enumerated on the next 

slide. Yes. 

So this was the record that was provided in NIOSH's 

response, and here's your max permissible values, 

and as you can see, you have the type of 

contamination. The air concentration, one is without 

masks, one is with a filter type masks, with a gray 

canister, and one is with positive air supply masks.

And then you have the permissible levels in that 

second column, and as you can see, for beta gamma, 

it just says ten to the minus eight.

And in the Site Profile, we recorded that it's three 

times ten to the minus eighth, which I believe is 
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61 

correct because if you look at this, this might've been 

just a convention of the day, but I believe that three 

times ten to the minus eleventh -- the three times I 

believe was intended to be repeated all the way down 

to all those other entries, for the mask entries and 

the air supply, positive air supply entries, because if 

you think about it, with respiratory protection, it 

offers you a protection factor against particles. 

And if this table were to be taken at face value -- in 

other words, that three times ten to the minus 

eleventh is only applicable to alpha without a mask, 

that would be indicating that you put on a mask and 

it had a different level of protection for particles 

containing alpha radiation than particles containing 

beta radiation.

And what we're looking at here is a protection factor 

of about 1,000. So –- 

Mr. Guido: Bob.

Mr. Barton: Yes?

Mr. Guido: I want to interject here because there's 

another version of this same table that's in 109-500, 

and it actually has a line between the three times 100 

-- it basically splits the three times ten to the minus 

eleven, and the one minus eight, and it splits each of 

those into separate cells, so that's a little bit clearer.

And also, the 1957 applied HP annual report 

specifically identifies the gross data actual level is 

one times ten to the minus eighth.

So you know, those are additional references, but 

when I put this response together, I just figured it 

would be -- you know, it would make sense that you 

wouldn't carry that three over, so I understand 

maybe we should've provided a little bit more 

clarification back then. 
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62 

But I think the weight of the evidence does show that 

it is one times ten to the minus eight, and I can 

provide the -- but the best reference is actually the 

1957 applied HP annual report where they discuss a 

release that occurred, and they specifically say that 

that release is greater than the administrative, you 

know, control limit of one times ten to the minus 

eight for beta.

And then the alternate version of this same table 

comes from a training document around that same 

period, and it's a little bit different.

I think it's a little clearer, although, you know, 

looking at what you're saying, it's not perfectly clear 

if the three would carry down, but it is split, the cells 

are split, and that's in SRDB 109-500. 

Mr. Barton: I'm looking at this, and maybe this table 

is an error in the Sadowski reference from 1953, but 

I mean if you put on a mask, your permissible level 

goes from three times ten to the minus eleven just 

to one times ten to the minus eighth? 

I mean it doesn’t make sense that if you start at three 

times ten to the minus eleventh, your protection 

factor from a mask is not going to be decidedly 

different for alpha than the protection factor from the 

mask for a particle that has beta radiation.

I mean --

Mr. Guido: Yeah, I don't dispute what you're saying, 

I'm just saying what the documentation, it's pretty 

clear from the documentation that the limit was one 

times ten to the minus eight for beta. 

I can't comment on the other, although you could 

look at that -- if you look at that training document, 

it does provide some clarification of those 

intermediate values that might help. 
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63 

I mean I think all of this is not super important for 

this discussion, but just a point of clarification.

Mr. Barton: And that's fair. If there's a better 

reference out there, that certainly clears this up. 

I mean I believe this was provided in NIOSH's 

response, which is why we put it up here. And maybe 

this is an error, or perhaps it maybe even changed 

between 1953, and you said the other one was a 

1957 document?

Mr. Guido: Well the training document is of the same 

era because it's the same table, so that one is also a 

'53. 

You know, that's the training they provided on this 

same thing, so I think that's the same era as this, 

and you know, I mean if we look closer, we might be 

able to find other citations that identified the gross 

beta limit. It's just the easiest one here, you know, 

the one I saw that was glaring was in that 1957 

report.

But I don't believe this represents a change, 

although, you know, anything's possible. But like I 

said, if you take a look at that 109-500 reference in 

the SRDB, that training document, and see if that 

helps. I definitely would be –- I think it's fair for us 

to update RPRT-90 with some clarification here. 

You know, on my side, I just thought it was pretty 

clear that you wouldn't pull the number three down 

from what I've seen from ORNL's documentation. But 

you know, anyhow, I think we can clarify RPRT-90 as 

far as the, you know, where this number comes from. 

And then of course, there's an issue with the TBD 

revision eventually, so that number isn't used 

anywhere in the TBD, so it's kind of an innocuous 

value, but you know, it does need to get updated at 
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64 

some point.

Mr. Barton: Okay. And certainly as the discussion 

goes forward, and if this method is going to be either 

modified, tightened up, or what have you, that'll 

certainly be important.

It makes sense to me that based on this reference, 

you would pull the three down because you would 

have the same protection factor between alpha and 

beta. And that's the reason for that. But as you said, 

it may not be necessarily that important at this stage 

of discussions. 

Again, this just all goes back to one of the points of 

weight of evidence, one of the three points on 

whether the proposed approach from '47 to this later 

period is bounding, which is a separate question 

entirely really of whether it's appropriate to do that 

before you evaluate that sort of approach under IG006, which of course, we keep repeating it.

It wasn't relevant to RPRT-90 during its formulation, 

but certainly will be relevant moving forward. So 

we've gone through the bioassay, the in vivo, and the 

air concentration comparisons, and sort of the fourth 

one was the comparison of source term, or 

throughput of iodine as another basis for why this is 

bounding, and this moves to observation 6, which I'm 

going to skip ahead.

Unfortunately I did not have the foresight to put that 

right after this in the presentation, but I'm going to 

skip ahead to slide 56, which is observation 6, for 

those of you who don't have Zoom up and are 

following based on the PDF.

And this again goes back to that comparison of, well, 

how much iodine do you really have between those 

two eras, the '47 to '49 and '55 to '62, as a basis for, 

again, using that data for co-exposure, and again, it 
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65 

doesn't apply to the IG-006 criteria yet, which would 

have to be evaluated, but in a way, it's almost akin 

to not only the co-exposure guidelines, but also since 

you're extrapolating data you have to consider 

whether it's an appropriate surrogate -- and I know 

that's another loaded word -- that we usually restrict 

to comparison of data between different sites, but in 

a more restricted sense, was what was going on 

during that earlier period reflective of what was going 

on during the period for which we really don't have 

any data to use.

So and again, in what I showed earlier directly from 

RPRT-90, it was stated that, well, in the earlier 

period, you had between essentially 9,000 and 

43,000 curie per year in process, whereas in the 

unmonitored period, it's down to around 1,000 to 

3,000. 

And as we point out in our review, we believe that's 

really an apples to oranges comparison because 

you're looking at what's presumably the RaLa stack 

emissions based throughput, which was primarily 

done in the '47 to '49, to this later period, which the 

first two years have RaLa, '55 and '56, and then the 

later years -- or the entire period has commercial in 

varying extents, which we're going to look at under 

observation 6 here.

So, to that end, I do want to switch here real quick 

to one other excerpt from one of the reports, so give 

me one moment here.

So when we talk about radioactive lanthanum, which 

was one of the source terms -- the other one was 

commercial -- there we go. 

What SC&A had pulled from, and this goes back to 

the Finding 5 discussion, the source of Finding 5 is 

that these are the releases -- iodine releases from a 
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66 

site, this was put together as part of really an 

analysis of the effects that might have happened to 

off-site populations from the release of iodine, and as 

you can see here, and we pointed it out in Finding 5, 

the maximum curies released from the RaLa process 

was in 1956, this time period when you had very little 

to no monitoring data.

And the next highest one, that is in that period where 

you have the monitoring data that's being used or 

proposed for use during the unmonitored period, and 

it's slightly lower, as NIOSH pointed out. 

But I wanted to show really where this data came 

from that was the source of Finding 5, and really the 

gist of this goes back to source term because the 

source term and the throughput and the methods and 

the production really calls back to exposure potential. 

Are those sufficiently similar and/or bounding?

So I'm going to head right back to and continue the 

presentation. Sorry for jumping around here a lot, 

but I think it's important to see a lot of these things. 

Okay, and NIOSH's response, and again, it's a 

summary. If NIOSH wants to jump in, please do. 

But NIOSH agreed that the RaLa production 

processes and commercial production processes are 

different, but argues that, you know, these activities 

were done in the same areas with the same 

radiological conditions, and ultimately concluded that 

it was unlikely that in -- during this unmonitored 

period, were exposed to levels that would have 

triggered the monitoring program.

And I guess my initial comment on that is that, I 

mean, RaLa was done in building 3026D, as is pretty 

well documented in the Site Profile, the previous 

Evaluation Report, and various other sources during 

that period of interest. And commercial was done in 
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67 

a completely different building, 3028. I think you can 

actually see that on one of the maps that Dr. Hughes 

put up earlier that showed essentially a schematic of 

the site. They're different buildings and, you know, 

they may be 100 yards apart, you know, like a 

football field, but they are different buildings, so I'm 

not sure it’s the same area necessarily.

And the same radiological controls, and I think that 

inference is made because it was the same site, the 

same general HP program. But again, that's an 

assumption that I'm not sure was, you know, fully 

fleshed out in RPRT-90, to make that statement.

And then, you know, you really have this other 

statement that it would be unlikely that the workers 

were exposed to levels that would have triggered the 

monitoring program.

And again, we have IG-006 up here, and I know this 

is probably frustrating to a lot of people on the phone 

because we really reviewed this as if it was a 

complete feasibility study for dose reconstruction, 

when in reality for the most part it was a feasibility 

study of bioassay methodology and whether it can 

measure the different source terms on-site. 

However, in this case, it actually for radioiodine, it is 

an actual co-exposure analysis, so even though IG006 came afterward, a lot of the same concepts do 

apply and obviously moving forward, IG-006 would 

have to be used to evaluate any sort of co-exposure 

estimate.

And furthermore, I mentioned they’re in different 

buildings and that, you know, as we'll look at in a 

second, the commercial side, not the RaLa, but the 

commercial is decidedly different in '56 to '62 when 

you compare it to '47 to '49, so just purely 

commercial operations, they're very different.
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68 

There's a much higher source in this unmonitored 

period from commercial operations than in the '47 to 

'49 period, which there's a chart in here that I will 

show shortly that exemplifies that, but furthermore, 

the statement that, you know, it was unlikely that 

workers during this unmonitored period would've 

triggered the monitoring program, we really can't 

evaluate that because of the limited monitoring data 

that we have, personal monitoring data, and we can't 

justify that necessarily as a reason to apply the coexposure estimates for 1947 to 1949 because I think 

that data is simply lacking.

So to say that they definitely would've triggered the 

monitoring program, that may be true, and those 

records may be out there that we don't have, they 

may have been destroyed, or maybe the situation 

didn't exist, but there's a wealth of possibilities 

beyond just the exposure levels were low enough 

that they wouldn't have triggered the monitoring 

program.

I guess that's my point, and again, it's not that we 

have proof that the exposures were decidedly higher. 

If that evidence was out there, we're not having this 

discussion, but I think it's important to point out the 

limitations on the information you do have when you 

make inferences in the weight of evidence of 

applying, again, data from this earlier period to the 

later period.

And so, as I said, here's the production of commercial 

radioiodine, and so what I pointed out here is you 

have that '47 to '49 period, and you're down, it looks 

like below maybe 250 curie in a given year, and that 

was 1949.

And then you move forward to, again, this is the 

period, 1955 to '62, which is just after the currently 
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69 

established SEC Class, and you see commercial 

operations are significantly higher.

So, one, we felt the comparison which for the earlier 

period was looking at RaLa estimates, comparing it 

to the commercial estimates in the later period, we 

feel that's apples and oranges, and that was the gist 

of observation 6, in that to really make that jump to 

see if it's representative of this later period, you have 

to do some sort of comparison, not just the total 

amount of curie, but are they different? 

Are there different processes taking place between 

RaLa production and commercial iodine production? 

Because one thing to consider is, you know, RaLa --

the iodine is essentially a waste product. 

In fact, there's a quote in the TBD directly about this, 

the RaLa situation, that says, much of the iodine 

volatilized during the slug dissolving process was 

effectively removed from the dissolver off-gas stream 

by the reflux condenser and chemical scrubber in line 

before the gaseous waste went to the stack.

So it was really pulled out via vacuum and scrubbed 

through, and then released through the stack as 

more of a waste product, and the TBD goes on to say 

that liquid waste from RaLa operations, they went to 

the local tank farms. 

So as opposed to actually trying to take radioiodine 

for commercial purposes, where that's a product, in 

RaLa, it was really the waste stream.

And so, we felt that a discussion of the different 

exposure potential between the two different 

operations was warranted to be able to make that 

extrapolation.

And of course, that is a concept that is really sort of 

outlined in IG-006, so again, that may be something 
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70

moving forward that wasn't really considered during 

the formulation of RPRT-90, which is understandable.

I put this slide up here because it was just unclear to 

me, because I know we've run into it at some other 

sites, and maybe it's restricted to residual periods, 

but you know, in general, my impression was that 

commercial operations aren't usually covered by the 

program, whereas obviously the RaLa operations are 

a covered activity, so those are certainly relevant.

But I was curious and I was looking for some 

guidance, either from Dr. Roberts, or perhaps Tim at 

NIOSH knows -- is this really a source term, the 

commercial side, that needs to be considered?

Now, a lot of the times, if you can't differentiate 

between what's commercial and what's noncommercial, then you have to consider the whole 

thing as non-commercial, and I understand that, but 

given the magnitude of the operations, especially the 

commercial operations, as the main driver of 

radioiodine separation, I guess under the statutes, 

how does this apply?

Because a lot of these concerns are about, again, as 

I just enumerated, comparing commercial operations 

to this as a RaLa production, and maybe that's not 

even a relevant discussion that needs to happen.

So I'm looking for clarification on how this is 

interpreted. 

Even though they were commercial operations, are 

they considered -- you know, the DOE operates, but 

it's just for commercial purposes, are they simply 

considered with all the other iodine sources because 

they can't be separated, or is that really considered 

a separate source that's not actually covered or 

should be covered by this program?
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71 

I put this slide in here because it wasn't clear to me, 

and, you know, just the term commercial operations 

sort of raises the question in my mind, so I guess I 

throw out that question. Do these commercial 

operations really matter? Because again, on the 

previous slide, if you're comparing the actual 

production, this unmonitored period is significantly 

higher than the period where you have the coexposure data being composed. 

Dr. Taulbee: This is Tim. I'll take a stab at this, and 

please others can speak up if I say something in 

error. 

But from my understanding, if the exposure is 

occurring on a DOE site that is a covered facility, it is 

included, with the exception of if it was from the 

Naval Nuclear Propulsion Program.

And so, these exposures are actually covered from 

that standpoint because it was done within the 

confines of the ORNL site.

Mr. Barton: Okay. Thank you.

Dr. Taulbee: That's my understanding.

Mr. Barton: Okay. 

And it's sort of implied by the fact that a lot of 

discussion before 90 is about the magnitude of 

commercial operations, but I just wanted to make 

sure that that's clear, and we're not going down a 

discussion that may be irrelevant in the end. But I 

think that does clarify it, so thank you for that.

And let me just back up again to our sort of 

conclusion slide about radioiodine. And then I'll 

certainly open up the floor to any questions or 

discussion of what the path forward is.
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72

And again, this is kind of jumping back to Finding 5 

because we're talking about the different source 

terms and what's the magnitude, and we do agree 

that when you compare the highest years with stack 

emissions, it's pretty small.

NIOSH points out that it's a four percent difference 

between the highest that was seen for the Hanford 

slugs, which was in 1956, and the highest that was 

seen for I believe it is the graphite reactor slugs in 

1947.

The one thing I'll point out is that 1956 is the year in 

which RaLa process ended, and it ended sometime in 

October based on the documentation, I'm not sure 

when. And the two comparisons were between the 

total emissions. 

So 1956, you had emissions only going through 

October, but it's reporting the total. So the difference 

of four percent, if we start to think of it in terms of a 

rate rather than a total, it would be a little bit more 

than four percent, and so you'd have those extra two 

months if you were going to try to scale up to a rate 

per month during '56. It's not as small as four 

percent. 

It's going to be more like, you know, 24 to 30 

percent, somewhere there, depending on when you 

assume that the RaLa production actually ceased at 

ORNL, which again was sometime apparently in 

October of 1956, so the rest of 1956, no more RaLa, 

and no more RaLa after that. But again, the 

uncertainty still exists, and if you accept that you can 

use data from one earlier period to the other, you still 

have to use a lot of care to extrapolate, to ensure 

that those exposures are going to be bounding.

So first you have to decide whether it's appropriate 

based on the conditions, and then I think that it's 
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73 

prudent that you sort of go the extra mile to ensure 

that any estimates you put out there are going to be 

bounding.

And I throw out this example because it's actually in 

RPRT-90 that -- and this goes back to the source term 

discussion that occurred just prior to the radioiodine 

discussion, in which a fraction of the source term was 

assumed to be inhaled, and during that methodology 

NIOSH had added, as far as I can tell, a somewhat 

arbitrary factor of ten in that evaluation just to 

ensure it was conservative.

So that's the sort of policy base part of this that, you 

know, if we can determine that it is appropriate to 

extrapolate data from this earlier year to the later 

years, I think you have to be very certain that you 

are going to be bounding those exposures.

And again, sort of the four main points that were put 

forth to support that it is bounding, there are, when 

you flesh it out a little bit, you know, the data are still 

scarce, especially for bioassay, the data are nonexistent for in vivo until those last two years in the 

'60s, and I think there are still some questions about 

the comparison to air sampling, although as Joe 

Guido pointed out, perhaps those can be solved with 

examination of a few other references to really pin 

down that number, especially in what timeframe.

What timeframe were these different air sampling 

levels in place? 

And of course, that also begs the question of, you 

know, where were those samplers, and all those 

other questions that would fall under the IG-006 

evaluation process of co-exposure model.

So that ends what I have as far as radioiodine at this 

point. There are certainly some concerns. 
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74 

I think really what the Work Group should weigh --

and I'm not sure that this is going to be solved today 

because as was pointed out, this method was put 

together before we had IG-006, so it really needs to 

perhaps be, you know, colored in a little bit, about 

these different evaluation criteria, such as 

representation, the completeness of the records 

you're using to try to apply.

And then another kind of strange point here that --

it's not on this slide, but it certainly occurred to us at 

SC&A, was that, you know, '47 to '49 is part of an 

SEC period that it was determined that internal dose 

reconstruction was infeasible, and that included 

fission products, which obviously iodine is a major 

fission product.

I mean, that's the reason it's part of the RaLa 

production process, is because you're using freshly 

irradiated fuel. 

So you're taking data that was ostensibly deemed 

inadequate for internal dose reconstruction in '47 to 

'49, and applying it to a later period, and saying that 

for that later period it's feasible, but for the earlier 

period, it's again, ostensibly infeasible.

So that's another kind of facet to all this on 

evaluating the degree to which this method that's put 

forth represents the feasibility of dose reconstruction 

for radioiodine, and again, specific to this period 

established where there's very little data, '55 to '62. 

So I think that that pretty much sums up our 

concerns, and I certainly think it may be worth 

discussing today what maybe the path forward is, or 

it's entirely obviously up to the Work Group whether 

they want to close these out and wait towards seeing 

a modified co-exposure method, or keep them open 

until -- you know, I guess I just open up the floor 
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75 

either to questions or comments, or what have you.

Chair Roessler: Bob, I think I'll start with a comment. 

I think normally we'd have NIOSH respond in detail 

to all of your comments, but to me it seems like the 

amount of material you've presented and the 

complexity of it, that it really I don't think is possible 

to deal with in this Work Group meeting. 

I'll see what NIOSH has to say, but it seems to me 

that this should be left open and we should give 

NIOSH an opportunity to go over it in detail and 

respond in writing, and then we should take it up at 

our next Work Group meeting, and I'll just throw that 

out.

Member Field: I'd like to, if possible, just hear what 

Tim thinks. I'd really be interested in the question too 

about '47 to '49. 

Was it feasible back then to do dose reconstruction 

for iodine? I think that's an interesting question too. 

Maybe that’s (audio interference) you can respond 

briefly, Tim.

Dr. Taulbee: Okay. 

Member Field: It's a lot --

(Simultaneous speaking.)

Dr. Taulbee: I'll give this a quick shot. 

Well for one, let me start by saying that, you know, 

the co-exposure type of modeling will certainly be 

updated in the format of handling IG-006 for one 

thing. 

So, that will certainly be updated, and I mentioned 

that, you know, kind of before Bob went through this, 

we'd be tightening things up, but the general 
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76 

approach I'm not sure will be changing a great deal.

Keep in mind in that early time period when the RaLa 

was going on, we have a lot of thyroid monitoring 

data of workers in that time that we know were 

working with the radioiodine, or being exposed to 

radioiodine at that time.

That was why we chose that particular group. 

So, whether it applies, and you know, we believe it 

applies to the latter time period because it is 

bounding from that standpoint. 

That's our main basis here, and Bob has pointed out 

some weaknesses associated with that that we intend 

to tighten up and will address in the future from that 

standpoint.

With regards to your specific question, Dr. Field, 

about the infeasibility of previously, you know, at 

that same time, in addition to RaLa, there was a lot 

of other activities that were going on there from the 

internal dose standpoint, and fission products was 

one of them that we had difficulty estimating the 

dose from. 

Did we break out iodine specifically to say, oh hey, 

we've got data between '49 and '59, and say yes, we 

can do iodine? No, we didn't go into that level of 

detail. 

We knew we had an infeasibility with the fission 

products in general at that time period, and so we 

didn't go into detail to exclude certain radionuclides. 

So I kind of take exception to what Bob just stated of 

how can you use it from this standpoint. 

That wasn't the intent under SEC 89. It was a general 

global evaluation from that standpoint. Does that 
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77 

answer your question, sir? Thank you.

Chair Roessler: So Tim, what do you think about 

responding to this? Am I just overwhelmed by all that 

Bob mentioned, or is there some --

Dr. Taulbee: No --

(Simultaneous speaking.)

Dr. Taulbee: You're not overwhelmed at all because 

we are too. 

But he raises a lot of really good points here that, you 

know, in light of IG-006, that we can go through and 

begin to address and fill in in an OTIB for a coexposure model for iodine. 

Iodine will be one of the radionuclides that we 

obviously address there in a full co-exposure model 

that is compliant with DCAS IG-006. 

And so we will be developing that. So I guess in a 

sense, SC&A will have another crack at this after 

we've now heard what their concerns are with it, and 

hopefully we will address it all in that new -- or in 

that OTIB. 

Chair Roessler: So I'd like to hear what other Work 

Group Members think, but it seems to me we should 

leave this one open until NIOSH has a chance to 

respond to everything that came up. 

Member Beach: Yeah, Gen, this is Josie. I agree with 

that also, leaving it open.

Member Valerio: This is Loretta. I agree with leaving 

it open.

Chair Roessler: Okay, so I guess we should vote 

then. 
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78 

I think that was a vote, the Work Group agrees that 

they should stay open and allow NIOSH a chance to 

respond, and take it up in our next Work Group 

meeting.

Dr. Roberts: Hi, Gen --

Chair Roessler: Are there any comments, other 

comments or questions for Bob while we're on this? 

Dr. Roberts: Gen, this is Rashaun. I have received a 

request for a comfort break, but I wanted to check in 

with you and see if that's okay with the Work Group.

Chair Roessler: I think that would be fine. What do 

you recommend, about ten minutes?

Dr. Roberts: Sure. Is that okay for everybody, or do 

you need a little more time?

Member Beach: No, ten minutes works for me, 

thanks.

Member Field: Sounds good, thank you.

Dr. Roberts: Okay, so we'll be back at 1:05 p.m. 

Eastern.

Chair Roessler: Okay, thank you.

Dr. Roberts: Sure.

(Whereupon, the above-entitled matter went off the 

record at 12:54 p.m. and resumed at 1:07 p.m.)

Chair Roessler: Okay, so I think we have finished with 

Finding 5, and we're going on to Finding 6. 

Now, SC&A, in your report, you say that this finding 

is subsumed under Finding 3, and you recommend 

closure. Is that what you plan on this one?
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79 

Mr. Fitzgerald: Yes, and just a quick background. 

Basically in comparison with the treatment on the in 

vitro, for example, in Appendix A, we felt that there 

was very little to go by on the in vivo capability and 

NIOSH's Technical Basis Document. 

I'm not going to go through this, but this is on the 

bottom of page 11 of our report in a footnote just 

citing some of the programmatic concerns that 

connect with the in vivo whole body counting 

program at Oak Ridge. 

So, yeah, our conclusion is that certainly that needs 

to be treated, but that's something that ought to be 

addressed as part of the, you know, programmatic 

considerations that would go into the resolution of 

Finding 3.

So, we would recommend that, yes, we do believe in 

vivo ought to be given attention, and that can be 

done in the context of Finding 3.

Chair Roessler: Okay, then let's go --

Mr. Fitzgerald: That remains our recommendation.

Chair Roessler: Then let's go on to Finding 7.

Mr. Fitzgerald: Okay, Finding 7 is somewhat of a 

duplication of a scoping question that was raised I 

think in Finding 1. So here and again in terms of the 

scope of the RPRT-90, we're clear that it's not going 

to address D&D and deactivation, and the waste 

management, and that should be closed for -- you 

know, again, it's part of Finding 1, so we recommend 

closure of that.

Member Beach: Gen, are you on mute?

Mr. Fitzgerald: I believe Gen's on mute.
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80 

Chair Roessler: I was on mute, thank you, Josie. Yes, 

I made a motion for the Work Group that we 

recommend closure of Finding 7.

Member Beach: Yeah, this is Josie. I agree with that 

and 6, as well. I know we breezed right past that one.

Chair Roessler: Yeah, well, we kind of combined that 

with Finding 3, but maybe just to make it completely, 

we should recommend closing Finding 6, too, then. 

No, I'm sorry, is that –- 

Mr. Fitzgerald: Yeah, certainly on Finding 6 we 

wanted to emphasize that we do believe that in vivo 

needs to be addressed, if nothing more than the 

experience we had at Los Alamos. 

It really, in terms of how it applies and what the

implementation is, that should be part of the 

assessment that we talked about in response to 

Finding 3.

Chair Roessler: You are not recommending closure of 

Finding 6, then? 

Mr. Fitzgerald: Only that it's subsumed by Finding 3. 

Finding 3 actually does cite in the finding statement 

in vivo, so if anything, this provides emphasis, but it 

could be considered part of Finding 3 as well. 

As long as the Work Group and NIOSH both 

understand our concern on that one, I think it can be 

handled by what Tim has offered as, you know, the 

revisions. 

Chair Roessler: So perhaps we should restate the 

motion then on Finding 6 that we recommend closure 

of Finding 6, since it is subsumed under Finding 3?

Mr. Fitzgerald: I'd be fine with that.
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81 

Chair Roessler: Okay. Work Group? 

Member Field: That sounds good, Gen.

Member Beach: Yeah, Gen, I agree with that. Thank 

you.

Member Valerio: I agree with that too, Gen. Thank 

you.

Chair Roessler: Okay, so then I think we took care of 

that, so then we go to Finding 7, and I think we, on 

that one, the Work Group agrees with SC&A's 

recommendation for closure of Finding 7. 

Member Beach: Okay, just one quick question on 

that, and maybe to Joe. 

Your paperwork says that Finding 7 is addressed in 

Finding 1, and we closed Finding 1, so I just want to 

make sure that we're still okay with the Finding 7?

Mr. Fitzgerald: Yeah, there's a little bit of duplication 

because I think Finding 1 is speaking to what in fact 

the scope of RPRT-90 actually is. 

And this one speaks specifically to D&D and waste 

management, so to some extent the answer for 

Finding 1 does satisfy Finding 7, as well. 

Member Beach: Okay, I just wanted to make sure I 

was clear, thanks. And I agree with closing it, Gen.

Chair Roessler: Okay. And I think we have the vote 

from the others. 

So I think we're ready then to move on to the 

observations. We have, SC&A brought up six 

observations. 

I think we've taken care of Observation 6, so then 

let's go back and start with Observation 1. 
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82 

Dr. Buchanan: Okay, this is Ron Buchanan with SC&A 

and I'll be discussing the observations that remain. 

And we see that Observation 1 was -- you want to go 

back one, Bob? 

Okay, observation 1 was concerned with inventory 

discrepancy, and in that, I might expand a little bit in 

that we found in 72 and 73 and also 76, we were 

given an Excel spreadsheet that had the inventory in 

it, and we were comparing it with what was in the 

original RPRT-90.

However, we found that there was some additional 

information in RPRT-90 that we couldn't find in the 

spreadsheet, and so that's where we came up with 

this observation.

Okay, next slide, Bob. Okay, NIOSH responded that 

the inventory of the radionuclides processed by the 

isotope group was developed through a review of the 

published sales records, and that's what we were 

referring to, and that's the spreadsheet we were 

using.

However, NIOSH updated that inventory sheet by 

reviewing logbooks, and this review resulted in

additional radionuclides and years, which were used 

actually in the report finding.

Next slide. 

So, we went through the spreadsheet and the 

inventory and we found the discrepancies that we 

had previously identified appearing in Table 7-2 and 

also 3 and 6. 

We concluded that the additional radionuclides or 

years from the logbooks added to the X-10 inventory 

original spreadsheet would explain these 

discrepancies. 
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83 

And we found that -- we did some spot checking and 

found that they agree, so next slide, Bob.

So, we find this observation's been clarified and 

recommend closure. Do you want to discuss each one 

of these afterwards?

Chair Roessler: Yes, I think we should, and I have a 

question of Rashaun. 

On the observations, which according to my definition 

are things that have a minor effect or no effect at all 

really on things, does the Work Group still take a 

vote? 

Dr. Roberts: No, I think you can just discuss, you 

know, the observation and see if anything remains to 

be done by NIOSH or SC&A.

Chair Roessler: Okay, so anyway, on Observation 1, 

SC&A recommends closure, so I think we can then 

move on to Observation 2.

Dr. Buchanan: Okay, Observation 2 was concerning 

the specific alpha-emitting radionuclides needs to 

identify for dose reconstruction. Next slide. 

Okay, so what I need to clarify here is that the 

original X-10 bioassay cards, and that's what the 

bioassay cards are provided at the time the bioassay 

was taken, was provided by Oak Ridge for individual 

claimants and are the basis for the DR.

Now, in addition to that, there's an X-10 database, 

and that database contains some of the essentials for 

the bioassay cards, but not all. 

It doesn't always identify the radionuclides. 

And so, and NIOSH responded, it will not be used for 

dose reconstruction purposes, but only the original or 
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84 

copies of the bioassay cards will be used. 

So next slide. 

So, our response is that considering NIOSH's 

clarification that the database will not be used for DR, 

and also the X-10 database only used for coworker 

intake modeling without further consideration of 

specific alpha-emitting radionuclide, and SC&A finds 

this observation's been clarified and recommends 

closure for Observation 2.

Chair Roessler: Okay, so then I think we can move 

on unless somebody has questions or comments on 

Observation 2.

(No audible response.)

Chair Roessler: I don't hear any, so go ahead.

Dr. Buchanan: Okay, Observation 3, okay. This is the 

trans-plutonium radionuclides, I need further 

analysis. 

Next slide, Bob. Okay so, another way of explanation 

here is that the TBD for Oak Ridge identifies 

americium-241 as the default assumption for transplutonium, the TPO bioassay results.

Now, NIOSH's response was that 20 of these 

radionuclides detect a TPO method of 20. 

Only two have a higher organ dose reconversion 

factor than DCF, and that is curium-248 and 

californium-249. 

And so, considering the americium-241 inventory is 

much greater by orders of magnitude than inventory 

of either of these two radionuclides.

Next slide.
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85 

And so, SC&A analyzed NIOSH's response and 

considering these DCFs, which we looked through 

those and the inventory amounts from the TPOs, we 

find that americium-241 as a default radionuclide 

provided, you know, other information that's not 

given for the individual dose reconstruction to be a 

reasonable assumption, so we found this observation 

had been clarified and recommend closure.

Chair Roessler: Okay. So again, unless there are any 

questions or comments, let's move on then to 

Observation 4.

Dr. Buchanan: Okay. 

Observation 4 has two parts, and this is concerned 

with use of gross alpha or gross beta counting data, 

which in Section 4 of RPRT-90, they list some codes 

and give you gross alpha or gross beta. 

And so, unless you know the radionuclide, then you 

could have some underestimated assigned dose, and 

then what you use as a substitute. 

Now, the two parts to this question, ruthenium-106 

in particular -- so next slide -- we see that in Table 

7-3, that ruthenium-106 was indicated as green, 

which it indicated that there was inventory bioassay 

method and bioassay data. When we tried to go back 

to the original source, we could not find any bioassay 

data for that period, for that isotope, and NIOSH's 

response was that this was an error in editing, and 

the revised Table 7-3 will show yellow, indicating for 

these years for ruthenium-106, indicating it was in 

inventory, there was a method available. 

There was no bioassay data. So next slide.

So, we concur with NIOSH's response and agree that 

the issue can be resolved by changes in the next 

revision of RPRT-90. 
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86 

That was the first half of Observation 4. 

Observation, you know, the second part was that the 

X-10 bioassay cards are provided for the claimant on 

our basis for the DR -- this is NIOSH's response, and 

claimant records for specific radionuclides, they were 

monitored and available for use in claimant-specific 

DRs, and specific adjustments based on individual 

radionuclides outside the scope of RPRT-90.

Next slide. 

Okay, so our concern about this is that it doesn't 

appear to address the conversion of counts per 

minute or dpm or microcuries to a intake. 

And perhaps this is more applicable to a revision in a 

coworker model, except if you have a bioassay card 

that just lists gross beta or gross gamma, or just dpm 

to microcuries without any specific radionuclide, then 

how would you handle it for a particular DR besides 

a coworker model?

And so, that was our main concern about this. Next 

slide, please.

So, we realized -- go back one now -- although RPRT90 is not intended to be a guide for step by step for 

DR, we feel that if some of the data that we're going 

to use for each individual dose reconstruction does 

not contain the full information and then how else at 

the address.

And so, we recommend that the observation be 

discussed or remain open, whatever's appropriate.

Chair Roessler: Okay, it seems like NIOSH could 

respond to this.

Dr. Hughes: Oh.
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87 

Dr. Taulbee: Go ahead, Lara.

Dr. Hughes: No, I don't have any, you can go ahead. 

I was just going to say about this, a lot of this, would, 

you know, depend on individual DR, and that's 

beyond scope of this report, but we can certainly add 

a little detail in the revision of RPRT-90 if needed.

Dr. Taulbee: That's correct. 

I think we can add a little more information that this 

will be considered in RPRT-90, but really where this 

will be most addressed is in the co-exposure model 

from that standpoint, which does provide specific 

instructions to dose reconstructors on how to use 

these results and what those assumptions are. So –- 

Chair Roessler: Well, this one --

Dr. Buchanan: That would be –- 

Chair Roessler: Go ahead.

Dr. Buchanan: Oh, excuse me. Yeah, but that would 

be, you know, for somebody that wasn't monitored. 

What about a person that was monitored? 

Where would that be addressed on how to convert 

cpm or dpm or microcuries to a particular intake if 

you don't know their isotope or the counting 

efficiency?

Dr. Taulbee: The Technical Basis Documents go 

through for dose reconstruction how to interpret each 

of the bioassay, and so, if you go to the internal 

Technical Basis Document for X-10, there is some 

guidance in there, but I'm not sure that it goes into 

the details of the exotic radionuclides from that 

standpoint.
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88 

Mr. Barton: This is Bob. So would that then be 

considered not only perhaps a revision to RPRT-90 to 

say, you know, this is beyond the scope, but 

guidance will be provided to the dosimetrist how to 

interpret it, and that information belongs in the TBD, 

and so it also would require an update?

It seems to also, the TBD -- and maybe that gets 

addressed on the adjustments you'd have to make in 

the co-exposure development, and that information 

just gets ported over? 

Is that essentially what you're saying, Tim? 

Dr. Taulbee: I'd have to go actually back to the TBD 

and re-read the entire internal section because there 

could be information in there saying if you run into 

one of these other radionuclides, what to do.

That's not on the top of my head as to what it states 

here, so you know, we'd have to go back to that, and 

I guess get back to you, so if you want to, you know, 

leave it open, then we can answer it, you know, later.

I just don't have that information on the top of my 

head. 

I don't know if anybody from the ORAU Team does, 

but, you know, if you do, speak up, if you don't, then 

we'll get back to you all. 

Chair Roessler: So why don't we leave it –- 

Dr. Buchanan: Okay, I'm okay with it. 

Chair Roessler: So we'll leave this one open and go 

on to Observation 5.

Dr. Buchanan: Okay. Observation 5.

Now this kind of relates back to Observation 1 with 

a detail on Table 7-6, and the results, we talked 
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89 

about 7-6 before, 7-6, where we had estimated dose 

from the problem radionuclides. 

And what this has to do was, we was trying to 

recalculate the doses and verify them, and we found 

out that the inventory didn't match what we had on 

our spreadsheet that was in the RPRT-90. 

And so, but that has been explained. Next slide, 

please.

Okay. And so, what we found out was that the RPRT90 was using the additional information in the 

logbooks and such, and so that was some updated 

years, updated inventory.

And so, this was also supplemented, Table 7-6 was 

supplemented by some information in the NIOSH's 

2020 response in their table 3 of page 12 of that 

response.

And we went back and filled in the blanks, and used 

that inventory then. Next slide, please. Bob. Okay. 

So we found that the observation had been 

addressed and we agreed with that, and so we 

recommend that this observation be closed.

Chair Roessler: Okay, so that takes us through all the 

findings and -- because we took care of Observation 

6, I believe, so we looked at all the findings and all 

the observations. 

Does SC&A have anything else to add?

Mr. Fitzgerald: Yes, I have one. This is sort of a 

comment or a question for NIOSH. 

You know, SEC 186 -- which is one of the SECs for Y12, this is all employees through 1957 -- is based in 

part on inability to dose reconstruct exotics 
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90 

generated at the calutron. And I know RPRT-90 was 

reserved for X-10 and Y-12, so I guess my question 

is, given that there's an SEC Class defined based on 

exotics generated at the calutron, it overlaps the 

period that RPRT-90 is examining, what are the 

implications for, you know, the feasibility assessment 

that RPRT-90 is doing for isotopes, you know, given 

that the decision that was made for Y-12? 

Because it appears there's definitely an overlap on 

the source terms that were being generated by 

calutron, and presumably being transferred over to 

Oak Ridge National Lab for processing. 

Dr. Taulbee: Well, that's a very difficult question to 

answer off the cuff here.

(Simultaneous speaking.)

Mr. Fitzgerald: Oh, no, and I think that's why I said 

it was more of a question/comment because I found 

that rather interesting, and I'm not sure, and 

certainly, you know, it may take a little digging what 

the implications are of that definition --

Dr. Taulbee: I mean, keep in mind --

Mr. Fitzgerald: For that time period of Y-12.

Dr. Taulbee: Keep in mind when we are doing some 

of the SEC evaluations, when we find an infeasibility 

for a particular radionuclide or for a set of 

radionuclides, many cases, we stop the evaluation, 

okay?

We don't go into more detail, we've got an 

infeasibility, we'll present it to the Board and we go 

with, you know, in this case, Y-12 to a designated 

SEC.

And so, you know, we'll say something like exotic 
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91 

radionuclides, that means there's one of them, we 

can't separate who was exposed to what, and so, 

we'll put it all into the Class in a sense.

That doesn't mean there aren't some of them in there 

that we could estimate, you know, from the current 

co-exposure modeling methodology. 

We didn't go into, you know, that level or great detail 

from that standpoint.

Should we have been more specific? Possibly. 

You know, in the past, you know, it's just this 

radionuclide and these others, you know, we can do 

it precisely.

So I would have to go back to the Y-12 and see what 

that basis was, and then compare it with what came 

over from Y-12 to X-10. 

X-10 really only applies which radionuclides came 

from Y-12 into X-10. Okay? The ones that were 

produced at Y-12 and stayed at Y-12 and were 

shipped out from Y-12 don't apply to X-10, even if 

they were ORNL workers. Okay?

Mr. Fitzgerald: Right.

Dr. Taulbee: So, there's that distinction there that we 

have to try and make sure we keep separate between 

the two facilities, and we have to be really careful 

here, so I can't answer your question off the cuff.

Mr. Fitzgerald: Yeah, and I guess I would just say, 

and leave it at that, just in the follow-on assessments 

that are planned, maybe some reconciliation of that 

SEC Class definition based on exotics on the calutron 

and whether it has any implications for isotope 

production, the survey that's being done under RPRT90? 
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92 

That would be the only comment I would make.

Dr. Buchanan: Thank you.

Chair Roessler: Okay, thank you, Joe. So I think then 

we're at the end of our evaluation of the report. 

What I think we have before us -- and I'm going to 

look at my notes here and see if I do it right -- I think 

Finding 3 and Finding 4, which are still open, we're 

really not sure when we're going to be able to follow 

through on that, so I think that'll just stay on the 

table. 

However, Finding 5, we have quite a bit to talk about, 

and I suggested maybe we wait until NIOSH puts 

together a response, and then we hold another Work 

Group meeting.

Does that sound feasible?

Member Beach: Yeah, Gen. This is Josie. It does to 

me.

Member Field: Yep.

Dr. Taulbee: Can I ask a clarifying question? With 

regards to Finding 5, would you prefer to see that as 

a full co-exposure model, or as an interim product? 

Just for guidance on our part. 

You know, if we put the iodine together, separate 

from the other exotics, would you want to look at that 

all together with the other exotics, or kind of interim?

Chair Roessler: See if Bob can respond to that one.

Mr. Barton: Well, I think a lot of the concerns may 

only be addressed when we see a full co-exposure 

model for it, so I'm not sure how much would be 

taken care of by an interim update to the analysis. 
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93 

You know, again, I think a lot of these questions are 

overarching, how do you reconstruct radioiodine for 

this period when you certainly have no data?

And some of the questions may even extend into the 

period after this, about when it is clearly feasible to 

reconstruct iodine, and obviously that's been made 

very clear. 

That was not the intent or the scope of RPRT-90. 

Maybe Tim's question is whether iodine should be 

separated out completely from the co-exposure 

effort. 

Just because it has somewhat of a different general 

approach using thyroid monitoring and extrapolating 

from another period.

I guess I'm not sure. 

It's tough to say until we see what the interim report 

does and does not evaluate, but I think a lot of our 

questions might only be answered completely when 

there's a complete co-exposure model on the table 

that addresses all of the criteria in IG-006 and 

extrapolating using sort of a surrogate dataset for a 

different time period. 

I think those would only really be addressed through 

a full co-exposure model to address feasibility.

I mean, we can certainly maybe knock some of the 

concerns out with an interim product, but again I'm 

not sure the entire issue of iodine would go away until 

the co-exposure model is completed. 

Dr. Taulbee: Okay. Then what I would recommend to 

you, Gen, is that Finding 3 and 5 will be kind of 

addressed in a full co-exposure model for the ORNL 

site. 
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94 

And we'll put that on the schedule for -- well, I think 

it's already on the schedule, but I'm not sure of that, 

but I don't know the date of when we'll be starting 

that effort.

Chair Roessler: Okay. And so, and then you're clear 

on Finding 5, too?

Dr. Taulbee: Right, Finding 5 will be incorporated in 

that, that full co-exposure model. 

We'll go through and address each of what SC&A has 

raised here under Finding 5 with regards to the 

iodine, and then they will have the ability to review 

that full model, in light of IG-006. 

Chair Roessler: Okay, so I'm satisfied that we've 

covered everything. 

And I want to make sure everybody else does, but I 

do want to comment that I'll have to make a report 

on this at the August Board meeting, and I would like 

to have -- I will need some help on putting that 

together, and I wonder if either Bob or Tim or Lara 

could help me draft something?

Dr. Hughes: Gen, this is Lara, I'd be happy to. 

I'm usually sending out a summary of the NIOSH 

path forward or to-do list after the meeting, so 

hopefully that should help, and then if you need 

additional detail, I'd be happy to write something up. 

Chair Roessler: Okay, so you have volunteered to 

draft something for me. Very good, thank you. 

So are there any other things we need to deal with, 

either Rashaun or Work Group members, or anybody 

else?

Dr. Roberts: Yeah, just to follow on to your question, 
This transcript of the Advisory Board on Radiation and Worker Health ORNL (X-10) Work Group, 

has been reviewed for concerns under the Privacy Act (5 U.S.C. § 552a) and personally identifiable 

information has been redacted as necessary. The transcript, however, has not been reviewed and 

certified by the Chair of the Worker Outreach Work Group for accuracy at this time. The reader 

should be cautioned that this transcript is for information only and is subject to change.

95 

your planning for August, Gen, I just wanted to check 

in and see -- I think we tentatively allocated an hour 

for this Work Group's update. 

Is that too much, too little?

Chair Roessler: It sounds like too much. What do you 

think, Lara?

Dr. Hughes: Yeah, that was actually one of the 

questions I had, if, you know, there's a desire to have 

a full presentation for NIOSH to summarize this Work 

Group meeting, or if we're just going to have a verbal 

discussion? 

It is up to the Work Group, obviously. I'd be happy 

to provide like a PowerPoint presentation update, if 

needed.

Dr. Taulbee: I understood what Gen was saying. 

Gen, you were going to give the presentation and 

we're just going to help you make the slides for that 

presentation, correct?

Chair Roessler: If that's okay with everybody, I'd do 

that.

Dr. Taulbee: Okay.

Chair Roessler: Okay. 

(Simultaneous speaking.)

Member Beach: That seems reasonable, Gen.

Chair Roessler: Okay, so you think an hour is good, 

Josie? 

Member Beach: Well, it just depends on questions. I 

doubt that you'll speak for an hour, but perhaps 30 

minutes. What do you think, Gen, I mean, as far as -
This transcript of the Advisory Board on Radiation and Worker Health ORNL (X-10) Work Group, 

has been reviewed for concerns under the Privacy Act (5 U.S.C. § 552a) and personally identifiable 

information has been redacted as necessary. The transcript, however, has not been reviewed and 

certified by the Chair of the Worker Outreach Work Group for accuracy at this time. The reader 

should be cautioned that this transcript is for information only and is subject to change.

96 

- 

Chair Roessler: Oh, I'm thinking 30 minutes would 

cover it, if Lara sort of agrees with that. For speaking.

Dr. Hughes: Yes.

Chair Roessler: And I kind of doubt that we'd have 

many questions, but I don't know.

Dr. Roberts: Okay, I'll make a note for 30 minutes.

Chair Roessler: Okay, and I'll go fast.

Dr. Roberts: Okay. Thirty-ish. 

Chair Roessler: Is there anything else –- 

Dr. Roberts: Okay.

Chair Roessler: Is there anything else we need to 

take care of at this meeting?

(No audible response.)

Chair Roessler: Okay, then I thank Rashaun and 

unless we hear something very quickly, let's adjourn.

Dr. Roberts: Sounds great, nice job.

Mr. Barton: Oh, Gen, I was just going to add that 

insofar as the SC&A can help collaborate with Dr. 

Hughes and NIOSH about putting together basically 

a summary of what was discussed today, you know, 

we serve at your pleasure, so just let us know how 

we can help.

Chair Roessler: Okay, well I'll have you take a look 

at it for sure.

Mr. Barton: Thank you. 

Chair Roessler: Okay.
This transcript of the Advisory Board on Radiation and Worker Health ORNL (X-10) Work Group, 

has been reviewed for concerns under the Privacy Act (5 U.S.C. § 552a) and personally identifiable 

information has been redacted as necessary. The transcript, however, has not been reviewed and 

certified by the Chair of the Worker Outreach Work Group for accuracy at this time. The reader 

should be cautioned that this transcript is for information only and is subject to change.

97 

Dr. Roberts: Great. 

Chair Roessler: Thanks to all of you. 

Dr. Roberts: Thank you.

Chair Roessler: All right, bye.

Dr. Roberts: Bye-bye.

Dr. Taulbee: Thank you all.

Chair Roessler: Bye.

Member Beach: Thank you. Bye.

Adjourn 

(Whereupon, the above-entitled matter went off the 

record at 1:38 p.m.)