Defense Threat Reduction Agency 


8725 John J Kingrnan Road MS 6201 


Ft Belvoir, VA 22060-6201 


December 22,2005 

James W. Neton, Ph.D. 

Office of Compensation Analysis and Support 

The National Institute of Occupational Safety and Health 

4676 Columbia Parkway, MS C-46 

Cincinnati, OH 45230 

Dear Dr. Neton: 

This letter responds to your e-mail of October 25,2005, which included a copy of the 

National Institute of Occupational Safety and Health (NIOSH) evaluation of Special Exposure 

Cohort Petition 00020. The proposed class definition includes all Department of Energy (DOE) 

employees, DOE contractors, or subcontractors employed at the Pacific Proving Ground (PPG) 

from 1946 through 1962. The evaluation notes that ". . .the sum of information from the 

available resources is insufficient to document or estimate the potential maximum internal 

exposure to members of the class.. ." and specifically references the Department of Defense 

(DoD) Nuclear Test Personnel Review (NTPR) Program. After reviewing it, I feel compelled to 

provide feedback on a number of serious misconceptions, as it appears that the authors were not 

fully aware of the current operating status of the NTPR Program. Equally concerning are several 

misrepresentations of a National Research Council (NRC) report in the evaluation. 

As you know from previous interactions between our two agencies, the NTPR Program 

possesses over twenty-five years of experience in supporting veterans and DoD civilian 

employees and contractors who were potentially exposed to radiation as a result of their 

participation in U.S. atmospheric nuclear testing or the occupation of Japan. The program has 

also produced andlor published an extensive body of technical documentation concerning both 

PPG and Nevada Test Site (NTS) tests and has completed thousands of dose reconstructions for 

veteran participants. The program has been the subject of numerous external reviews, most 

recently by the NRC ("A Review of the Dose Reconstruction Program of the Defense Threat 

Reduction Agency," 2003). 

My staff and I have reviewed the NIOSH evaluation report and compiled several 

comments for your consideration (enclosed), and I would like to highlight a few of them here: 

The technical arguments that support the conclusions of the evaluation appear to be based 

on a selective citation of factual information from the 2003 NRC report. I'm 

disappointed that the evaluation cites only the deficiencies identified in section V.C.3.2 

of the NRC review (factors tending to underestimate inhalation dose), without any 

consideration of the countervailing factors in section V.C.3.1. The NRC committee 

specifically attempted to discourage this practice (p. 2 10): 
"The committee also emphasizes, however, that the discussions of assumptions 

summarized in Table V.C.7 should not be used to draw conclusions about whether 

estimates of inhalation dose to atomic veterans in particular scenarios provide credible 

upper bounds without consideration of the importance of assumptions discussed in the 

previous section that should tend to result in overestimates of inhalation dose. " 

Furthermore, there is no discussion of the overall perspective of the hTRC findings in 

regards to methods used by NTPR for estimating upper bounds of internal dose. 

Neglecting valid and important counterarguments may support your conclusion, but the 

resulting product fails to meet the stated goal of providing a fair and science-based 

determination. 

Section 7.1 specifically addresses NTPR dose reconstructions, noting that "In order for 

NIOSH to consider using the DTRA model for inhalation dose, the model must be able to 

establish credible upper bounds." In response to the 2003 NRC report, the Defense 

Threat Reduction Agency (DTRA) issued interim guidance (enclosed) that was intended 

to establish conservative upper bounds for dose reconstructions. Ongoing efforts to 

improve methods of uncertainty analysis will likely produce more credible upper bounds, 

thereby eliminating the need for interim guidance. 

Section 5.0 summarizes available monitoring data, but it appears that several useful DoD 

publications were not included in the review (enclosed). Some of these documents are 

publicly available on the DTRA website (http://www.dtra.mil) or at the NTPR reading 

library in Reston, Virginia. Many others are available through the DTRA Data Archival 

and Retrieval Enhancement (DARE) Program. Access to DARE is available to 

Government agencies, their contractors, and other authorized users on a need-to-know 

basis. 

I have also enclosed a review of the NIOSH evaluation report by Dr. David C. Kocher, a 

member of the 2003 hTRC committee. I wholly endorse Dr. Kocher's observations, which 

address unfortunate distortions of the 2003 NRC findings contained in the NIOSH evaluation 

report. He raises a number of valid concerns, not the least of which is the NIOSH interpretation 

that credible upper bounds of PPG internal dose cannot be established. While the NRC report 

concluded in section V.C.6 (p. 225) that the methods used by the NTPR Program did not 

consistently provide credible upper bounds, it did not imply that credible upper bounds could not 

be established. 

One could argue that the NIOSH decision to recommend Special Exposure Cohort status 

for the proposed class may be a proper policy decision. However, the conclusion of this 

evaluation, namely to treat the proposed cohort presumptively, appears to be insufficiently 

supported by an incomplete technical analysis despite a search for relevant information. 

Additionally, I must object to this evaluation on the basis that the NTPR Program has 

successfully implemented a credible solution for providing defensible dose reconstructions in 

support of federally-mandated entitlement programs. In this regard, the NTPR Program 

currently has methods in place that could acceptably assist hTIOSH in its support of the 

EEOICPA. 
In conclusion, I believe that DoD could be of significant assistance to your agency in 

supporting dose reconstructions for individuals involved in atmospheric nuclear testing. I can 

provide sample post-NRC 2003 dose reconstructions that we have performed for veterans 

involved in PPG testing. I also can make available to you the NTPR methodology that was 

developed for atmospheric testing, as well as the supporting data archives. I believe increased 

collaboration between our two agencies would be of great benefit. 

Sincerely, 

Paul K. Blake, Ph.D. 

Program Manager 

Nuclear Test Personnel Review 

Enclosures: 

1. DTRA comments on the SEC Petition 00020 Evaluation Report 

2. DTRA Interim Guidance of July 16,2003 

3. Selected list of publications containing information relevant to the Evaluation Report 

4. Dr. Kocher's review of the SEC Petition 00020 Evaluation Report 

Copies to: 

Chairman, Veterans' Advisory Board on Dose Reconstruction 

Chairman, Advisory Board on Radiation and Worker Health 
Subj: DTRA comments on the SEC Petition 00020 Evaluation Report 

NIOSH Finding 1: Lack of sufficient information from document search 

The Evaluation Summary (p. 2) states that NIOSH lacks access to sufficient information to 

estimate the maximum radiation dose incurred by any member of the class being evaluated, and 

that the sum of information from the available resources is insufficient to document or estimate 

the potential maximum internal exposure to members of the class, under plausible circumstances 

during the period in question at PPG. 

Section 4.2 (p. 6) indicates that the document search performed in support of this evaluation 

included the NIOSH research database, the Internal Dose Monitoring website of Lawrence 

Livermore National Laboratory, the DTRA website, the DOE Environment, Safety and Health 

webpage, and the Marshall Islands Document Collection. 

DTRA Response 1 

The document search appears to have excluded or overlooked the DOE Nuclear Testing Archive 

(http://www.nv.doe.gov/library/testingarchive.htm), the NTPR public library, and a restricted 

access, DoD data archive (DARE), arguably the largest archival collections of documents 

relating to U.S. atmospheric nuclear testing. As described, the search did not include the Los 

Alamos National Laboratory, which had scientific teams extensively involved in nuclear testing. 

It appears that at least one source of relevant information cited in the evaluation (the University 

of Washington) was not investigated, even though this information is likely obtainable from the 

Nuclear Testing Archive and/or DARE. 

NIOSH Finding 2: Availability of information and data 

Section 3.0 (p. 5) states that no data or documentation had been located indicating any results or 

program to monitor for internal exposure due to ingested or inhaled radioactive material, and that 

the petitioner’s declaration that there was no such monitoring was considered as suitable 

evidence in support of the belief that dose reconstruction would not be feasible. 

Section 4.1 (p. 5) indicates that NIOSH reviewed 65 cases meeting the revised class definition to 

determine whether internal and/or external personal monitoring records (or any other monitoring 

records) were available for the employee. While there was an external monitoring program and 

most claimants had external monitoring records, no records of inhalation or ingestion monitoring 

for these individuals at the PPG were available to NIOSH. References to individual internal 

monitoring were made in several historical reports on specific test series. 

Section 5.0 (p. 7) states that there was only brief mention in the Albuquerque Operations 

manager’s report of limited use of nasal smears, for which NIOSH has been unable to locate the 

associated data. 

Table 5.1 (p. 7) indicates that no internal dosimetry data were located in publicly accessible 

records and that SAIC confirmed that urine and air data for evaluation of internal exposures are 

not available. Furthermore, the table indicates that air sampling protocols differed by operation, 

but that samples were collected according to operational plan. However, no occupational air data 

had been retrieved to date. 

Enclosure (1) 
Section 5.0 (p. 8) refers to a report of the Albuquerque Operations Manager (the contents of 

which are cited as an example of data typically found in test reports), but NIOSH indicates that 

no data from these samples had been located and that no data regarding the number of samples 

collected at each test shot had been located as of the date of the report. This section also claims 

that NIOSH contacted SAIC regarding the availability of urine and air sample data for tests 

conducted at PPG, but SAIC technical experts indicated that the 2600 urine samples identified 

for CROSSROADS were unavailable and that few, if any, air sample data are available. 

Section 6.0 (p. 10) states that air sampling was performed during Operation CROSSROADS, but 

was designed to establish fallout patterns rather than monitoring occupational internal exposure. 

According to SAIC, few of these air sampling data are available and NIOSH had not had the 

opportunity to examine them. Urine samples were also collected but NIOSH had been unable to 

retrieve the data. After CROSSROADS, urine sampling was performed for special cases (there 

were 125 urine samples analyzed), but these data were not available to NIOSH. 

DTRA Response 2 

“Absence of evidence is not evidence of absence.” Admittedly, only limited internal monitoring 

results are available for Americans who were involved in the PPG tests. Examples of this data, 

retained in the NTPR public library, include special naval radiological medical exams that 

documented urine bioassay and film badge results, naval message traffic that summarizes 

Operation CROSSROADS urine bioassay results, and descriptions in veteran’s published 

recollections. Due to limited PPG internal monitoring results, DoD has determined internal 

doses based on extrapolation from the radiological environment (e.g. fallout data) and exposure 

conditions. The DoD internal dosimetry methods are documented in a number of technical 

reports available on the DTRA-NTPR website (see Enclosure (3)). 

In regards to NIOSH inquiries about the availability of internal monitoring data, SAIC technical 

experts do not recall any follow-up questions pertaining to the availability of air sampling and 

nasal smear data. Where the CROSSROADS urine bioassay data are concerned, an SAIC 

analyst indicated that he was not aware that the data in question were available in NTPR files. 

Because NTPR only requires access to data concerning specific participants (for the purpose of 

developing dose reconstructions in response to compensation claims or personal inquiries), this 

does not mean the data are not available to NIOSH. 

It may be worth noting that the original stated purpose of the CROSSROADS air monitoring (i.e. 

fallout monitoring) is generally irrelevant, as fallout sampling data can be used to determine 

airborne concentrations of radionuclides for use in the calculation of internal dose. 

NIOSH Finding 3 – Lack of access to required information 

Section 7.0 (p. 10) indicates that NIOSH must determine whether it has access to sufficient 

information to estimate the maximum radiation dose that could have been incurred under 

plausible circumstances or to estimate radiation doses more precisely than a maximum dose 

estimate. If NIOSH were to have access to sufficient information, then dose reconstruction 

would be deemed feasible. 

Section 7.2 (pp. 14-15) states that, although it might be possible to calculate the maximum 

plausible radionuclide deposition from the detonations, because there are so many variables (e.g., 

Enclosure (1) 
size and type of bomb, detonation height, geographical conditions, weather conditions, etc.), 

each test would need to be evaluated individually to determine the maximum exposed individual 

or group for that test. This would require access to potentially sensitive information specific to 

each nuclear device together with extensive information on employee locations and activities. 

As such, NIOSH has concluded that it cannot determine on a timely basis the feasibility of a 

source and process-based dose reconstruction effort. 

Section 7.4 (pp. 16-17) states that NIOSH lacks access to source term data, bioassay data or 

internal monitoring data to estimate internal doses associated with potential inhalation of 

radionuclides, and that methods used by the NTPR Program cannot be considered for application 

to EEOICPA dose reconstructions until issues identified by the NRC committee have been 

resolved. Consequently, NIOSH concludes that it is not feasible to estimate with sufficient 

accuracy internal radiation doses for the class of employees defined in this report. 

DTRA Response 3 

NIOSH was aware from inter-program communications over several years that clearances would 

be required to review the sensitive and classified data and information that are vital to producing 

a credible dose reconstruction (e.g. classified nuclear source and associated radiochemistry data). 

NIOSH made no request to DTRA for access to classified material. While the true and intended 

definition of “sufficient information” can be debated, it is unclear how one agency can consider 

the available information and data to be sufficient for dose reconstruction while another agency 

does not. 

Based on findings of the NRC review (section V.A), the NTPR Program established a detailed 

process to develop and document a personalized scenario of participation and radiation exposure 

for each veteran participant. Questionnaires, statements, and interviews (along with official 

reports and historical documents) form the basis of a participant’s location and activities, while 

personnel monitoring results and other radiological information are used to establish exposure 

conditions. The radiation environment is characterized in time and space, and matched with the 

activities and locations of the participant to determine exposure potential. As indicated in the 

NTPR interim guidance (July 2003), a participant’s recollections are to be reflected in the 

scenario unless demonstrably inaccurate. With over two years of experience in developing 

detailed participation scenarios since the NRC report was released, the NTPR Program has 

implemented a credible solution to improving communication and ensuring benefit of the doubt 

for veteran participants. 

NIOSH Finding 4: Urine bioassays at Operation CROSSROADS 

Section 6.0 (p. 10) reports that a urine bioassay program was implemented during Operation 

CROSSROADS. The report correctly states that 2,600 samples were tested, that men used 

instruments that were on hand and developed techniques, and that the presence of high 

background made it difficult to determine positive bioassays. 

DTRA Response 4 

The original source document from which this information was taken (Naval message 150802Z) 

was misquoted in DNA 6032F, as only 16 of the 2,600 men tested positive for beta activity in the 

urine. Nevertheless, the excerpted passage is incomplete, as the cited reference goes on the state 

that “the RadSafe Section reported slight beta activity had been found in the urine of 2,600 men 

Enclosure (1) 
checked. Despite all the concern and discussion...there is no indication in CROSSROADS 

documentation that positive alpha counts were found in any urine samples.” 

Short of consulting with NTPR technical experts, it is unlikely that NIOSH could have known 

that the cited reference contained erroneous information. However, it is disconcerting that a 

factual citation was taken out of context. Appropriate consideration of the excluded passage 

would seem to contradict the overall conclusion of the evaluation report (i.e. that suitable internal 

monitoring data are not available). 

NIOSH Finding 5 – Credible inhalation dose upper bounds 

Section 7.1 (p. 12) attributes the 2003 NRC report as concluding that the methods used by the 

NTPR Program to estimate inhalation doses do not consistently provide credible upper bounds. 

DTRA Response 5 

This statement, although correct, appears to have been taken out of context. The current usage is 

somewhat misleading, since the NRC committee judged that concerns about obtaining credible 

internal dose upper bounds at PPG are less important. According to the NRC report (p. 222): 

“[Studies] indicate that inhalation doses due to resuspension of longer-lived radionuclides in 

fallout deposited on residence islands in the Pacific are unlikely to be important in most 

cases.” 

It should be noted that several of the factors that potentially underestimate internal dose upper 

bounds (as listed in Table V.C.7 on the same page) are relevant only at NTS. If NIOSH wishes 

to continue quoting the 2003 NRC report in this manner, it would be entirely appropriate to note 

the following (NRC, p. 212): 

“An example of a scenario in which credible upper bounds in inhalation dose probably are 

obtained in dose reconstructions involves exposure to descending fallout throughout the 

period of descent. Such exposures occurred, for example, on residence islands in the 

Pacific.” 

NIOSH Finding 6 – Uncertainty in estimating radionuclide concentrations in deposited fallout 

Section 7.1 (pp. 12-13) outlines what NIOSH considers as the most significant NRC finding with 

respect to the feasibility of dose reconstruction for non-military personnel (from Table V.C.7): 

“Sources of error and uncertainty in methods of estimating radionuclide concentrations in 

deposited fallout based on measured external photon exposures have not been evaluated, and 

reliability of methods is unknown. The assumption of no fractionation (except for removal of 

noble gases) should result in substantial underestimates of concentrations of refractory 

radionuclides (such as plutonium).” 

DTRA Response 6 

The model used to assess internal doses based on external photon exposure is consistent with the 

methodology used in Federal Guidance Report No. 12, which includes dose conversion factors 

for external exposure based on concentrations of specific radionuclides distributed on the 

ground. There is a substantial discussion of uncertainties with these values, but the uncertainties 

Enclosure (1) 
were considered small relative to other factors involved in calculating internal dose for NTPR 

participants. Furthermore, the NIOSH evaluation does not reflect the NRC committee’s 

conclusion that the primary situation where the characterization of radionuclide concentrations 

contributing to internal dose could be a substantive issue is for blast-wave resuspension of aged 

fallout at NTS. 

Based on analyses in the NRC report (and considering all associated parameters and 

uncertainties and assuming that radionuclide compositions in atmospheric clouds are reasonably 

well-characterized on the basis of cloud sampling data), the NTPR Program concluded that 

reasonable upper-bound internal dose from inhalation was likely to be 3 to 10 times greater than 

the values being reported at that time. To remedy this potential underestimate, the program 

issued interim guidance (July 2003) to multiply existing calculations by 10 to obtain a credible 

upper bound (except in the situation of blast-wave resuspension of aged fallout in forward areas 

at NTS). 

Given the magnitude of the assessed PPG internal doses to date, the associated level of 

uncertainty is not likely to significantly affect the probability of causation for most claims. This 

observation was echoed by the NRC committee in section V.C.6 (p. 226): 

“Of paramount importance is the issue of whether deficiencies in methods of estimating 

inhalation dose identified by the committee could have affected decisions about 

compensation of atomic veterans. The committee believes that possible underestimation of 

upper bounds of inhalation doses by the NTPR program is unlikely to be unimportant for 

most participants in the Pacific or occupation forces in Japan. Inhalation doses to most of 

those participants probably were too low for possible underestimation of upper bounds to 

have affected decisions about compensation.” 

NIOSH Finding 7 – DTRA corrective actions 

Section 7.1 (p. 13) notes that DTRA and the Veterans Administration (with support from the 

National Council on Radiation Protection and Measurements) issued a joint report to Congress in 

June 2004 that outlined a plan of action to correct deficiencies identified in the 2003 NRC report 

within two years. The evaluation goes on to state that, in order for NIOSH to consider using the 

DTRA model for inhalation dose, the model must be able to establish credible upper bounds and 

that the issues identified by the NRC committee that “question the ability to establish upper 

bounds” would need to be resolved and the model would need to be validated. 

Section 7.4 (p. 16) concludes that the methods used by the NTPR Program for military 

employees cannot be considered for application to EEOICPA dose reconstructions until issues 

identified by the NRC committee are resolved. 

DTRA Response 7 

A significant portion of the NIOSH evaluation seems to revolve around the erroneous contention 

that DTRA has not revised the methodology for calculating internal dose upper bounds (and to a 

lesser extent, will not be finished until June 2006). Although this isn’t relevant to the feasibility 

of establishing credible upper bounds, there is no indication that NIOSH inquired about the 

current status of the corrective action plan, and the evaluation report includes no discussion or 

analysis of the interim guidance that was issued in July 2003. Consequently, NIOSH failed to 

Enclosure (1) 
investigate the possibility of using the NTPR interim methods for establishing credible internal 

dose upper bounds. It seems incongruous that a method can be considered sufficiently credible 

to one federal agency but not acceptable to another. 

The NTPR Program is confident that the interim guidance qualifies as progress toward 

establishing credible upper bounds. Corrective actions continue to be evaluated and 

implemented, and they will undoubtedly be reviewed by the Veterans’ Advisory Board on Dose 

Reconstruction. 

It is important to note that the NRC committee did not question the ability to establish credible 

upper bounds, but rather the credibility of the upper bounds that were being estimated at the time 

of the review. This contention is addressed by Dr. Kocher in more detail. 

NIOSH Finding 8 – Correction factors and assumptions 

Section 7.1 (p. 13) acknowledges that issues associated with NTPR external dose reconstructions 

(as identified by the NRC committee) are similar to issues that NIOSH has already encountered. 

NIOSH expects it could apply uncertainty factors to ensure a reasonable estimate of external 

dose and that the dose could be bounded by making claimant favorable assumptions to overcome 

data gaps (e.g. the assignment of a dose from the highest exposed group). 

Section 7.2 (p. 16) states that NIOSH can utilize film badge monitoring data or field radiation 

surveys to determine external dose, and if no acceptable film badge data are available, maximum 

credible exposure scenarios (with the appropriate application of correction factors for beta dose 

and uncertainty) could be developed for individuals given the roles, responsibilities, and location 

associated with the task unit they were assigned to and exposure rate information for various 

work assignments. 

Section 7.3 (p. 16) indicates that it is not clear whether individuals at the PPG site underwent 

chest X-ray examinations, but that NIOSH could make claimant-favorable assumptions 

regarding the frequency and the type of X-ray equipment used. NIOSH has published an official 

procedure for assigning dose from X-ray examinations, concluding that it is feasible to determine 

the maximum potential occupational medical exposures. 

Table 5.1 (p. 7) notes that suitable monitoring data to estimate intakes of radionuclides generally 

were not obtained (aside from a number of urine samples analyzed during Operation 

CROSSROADS). 

DTRA Response 8 

Although NIOSH seems to be comfortable with external dose correction factors and claimantfavorable assumptions to overcome a lack of data (for external gamma and medical X-ray doses), 

there is no rationale provided in the evaluation report that refutes the appropriate use of similar 

correction factors and assumptions to develop and ensure credible internal dose upper bounds. 

In this regard, the conclusion that NIOSH could not use the DTRA dose reconstruction process 

seems to be unfounded. 

Enclosure (1) 
NIOSH Finding 9 – Sufficient accuracy 

Section 8.0 (p. 17) concludes that it is not feasible for NIOSH to estimate with sufficient 

accuracy radiation doses from potential internal exposures. 

DTRA Response 9 

The definition of “sufficient accuracy” is not only vague, but it’s unclear how a requirement of 

accuracy pertains to credible upper bound doses. It would make sense that a most probable 

(mean) dose should be accurate. However, the requirement for upper bound doses is that they be 

credible (i.e. at least a 95th percentile estimate), as opposed to accurate. This contention is 

addressed by Dr. Kocher in more detail. 

NIOSH Finding 10: Health endangerment 

Section 8.0 (p. 17) states that doses from potential internal exposures may have endangered the 

health of some members of the proposed class, based on the “facts” that there was likely to have 

been some inhalation exposure to plutonium and other alpha-emitting radionuclides and the lack 

of reliable information to establish plausible maximum limits to this exposure. 

DTRA Response 10 

There seems to be no justification or evidence provided in the evaluation to support the 

conclusion that inhalation exposure was likely or that the potential exposure may have 

endangered the health of exposed individuals (especially since the evaluation repeatedly states 

that information and data were unavailable). As such, these “facts” of likely exposure and 

endangerment are more appropriately considered as assumptions, bordering on concessions 

(which are sometimes granted when there is no evidence to either prove or disprove a given 

hypothesis). 

Furthermore, it is unclear why there is a need to establish “plausible maximum limits” when a 

credible 95th percentile upper bound is already considered adequate and acceptable. Ultimately, 

it’s likely that most PPG doses (and the associated probability of causation) are well below the 

applicable threshold for compensation. Internal dose might not be relevant in all cases, or may 

not involve scenarios where the validity of the upper bound was questioned by the NRC. It 

follows that the assignment of SEC status to the proposed class would not be scientifically 

founded. This conclusion is substantiated in section VII.C of the 2003 NRC report (p. 263): 

“The committee notes that the established policy of using upper-bound estimates of dose 

(95th percentiles) with the more extreme lower-bound estimates of doses that correspond to a 

50% probability of causation of various cancers is highly favorable to the veterans’ interests. 

If credible upper bounds of dose are obtained in dose reconstructions, atomic veterans can 

be compensated for nonpresumptive diseases even when the true probability that radiation 

exposure cause the diseases is low. 

None of this is to say that the veterans do not have legitimate complaints about their dose 

reconstructions; in many cases, the committee believes they do. Rather, the committee hopes 

that veterans will understand that their radiation exposure probably did not cause their 

cancers in most cases and that reasonable changes in methods of dose reconstruction in 

response to this report are not likely to greatly increase their chance of a successful claim for 

compensation when a dose reconstruction is required.” 

Enclosure (1) 
NIOSH Finding 11: Miscellaneous corrections 

The table in Section 6.0 (p. 9) implies that Shot ABLE (Operation CROSSROADS) and Shot 

KING (Operation IVY) were airbursts, and reports that Operation DOMINIC I included only 

airdrops. 

Appendix A, Section 3.1 (p. 25) cites the yield of both detonations at Operation CROSSROADS 

as “23 KT.” 

DTRA Response 11 

According to DOE/NV-209 (and to maintain consistency with the convention used elsewhere in 

the evaluation report), Shots ABLE and MIKE should be listed as airdrops and it should be noted 

that DOMINIC I included underwater and rocket (airburst) detonations. The same reference lists 

the yield of the two CROSSROADS detonations as 21 kT. 

Enclosure (1) 




Subj: Selected List of Publications Containing Information Relevant to the Evaluation Report 

1. DoD publications applicable to this review are available under three categories: 

a. Unclassified and approved for public release; distribution unlimited. Many of these are 

available at the DTRA-NTPR website (http://www.dtra.mil). Others are available through other 

Government websites and in libraries across the country. 

b. Unclassified but limited distribution. In most cases, these are available to federal 

agencies and their contractors. These are available from DTRA’s DARE program. 

c. Classified. In many cases, these can be cited, although they are only available for 

review by individuals holding appropriate security clearances. 

2. NIOSH Evaluation, Table 5.1 (Internal Dosimetry Data) states that no data is available in 

publicly accessible records. The following unclassified documents that discuss internal 

dosimetry are available on the DTRA-NTPR website: 

a. DNA 6032F – Operation CROSSROADS 1946, Chapter 2.0, pg. 51. 

http://www.dtra.mil/toolbox/directorates/td/programs/nuclear_personnel/docs/DNA6032F.pdf 

b. DNA-TR-84-119 – Internal Dose Assessment – Operation CROSSOADS 

http://www.dtra.mil/toolbox/directorates/td/programs/nuclear_personnel/docs/DNATR84119.pdf 

c. DNA-TR-88-260 – Low Level Internal Dose Screen – Oceanic Tests 

http://www.dtra.mil/toolbox/directorates/td/programs/nuclear_personnel/docs/DNATR88260.pdf 

d. DNA-TR-86-120 – Analysis of Radiation Exposure, Service Personnel on Rongerik 

Atoll, Operation CASTLE, Shot Bravo, Section 4.0 

http://www.dtra.mil/toolbox/directorates/td/programs/nuclear_personnel/docs/DNATR86120.pdf 

e. DNA-TR-84-375 – FIIDOS – A Computer Code for the Computation of Fallout 

Inhalation and Ingestion Dose to Organs 

http://www.dtra.mil/toolbox/directorates/td/programs/nuclear_personnel/docs/DNATR84375.pdf 

3. NIOSH Evaluation, Table 5.1 (Environmental Sampling Data) describes only University of 

Washington and Public Health Service samples. Many unclassified and approved for public 

release DoD publications are available for review. The following is a small sampling of 

radioactive fallout documents available from DTRA’s DARE program: 

a. Item number: 08482 

Title: 4-pi Gamma Ionization Chamber Decay Measurements of Fallout Samples from Operation 

CASTLE 

Authors: Shipman W.H. ; Lai`J.R. 

Corporate Authors: Naval Radiological Defense Lab. (San Francisco, CA) 

Publication date: 5601 

Report Numbers: USNRDL TR 147 ; NRDL TR 147 

Enclosure (3) 
b. Item number: 08494 

Title: Activity Size Relationship of Fallout Particles from Two Shots, Operation REDWING 

Author: Chan H.K. 

Corporate Authors: Naval Radiological Defense Lab. (San Francisco, CA) 

Publication date: 5902 

Report Numbers: NRDL TR 314 

c. Item number: 20601 

Title: Solubility Characteristics of Radioactive Bomb Debris in Water and Evaluation of Selected 

Decontamination Procedures 

Authors: Lowe H.N. Jr. ; Lindsten D.C. ; Pruett P.B. ; Lacy W.J. ; Kennedy J.P. 

Corporate Authors: Army Corps of Engineers (Ft. Belvoir, VA.) 

Publication date: 19590212 

Report Numbers: AERDL TR 1569 

d. Item number: AFSWP 0155 

Title: Residual Radiation Pattern for Various Surface Wind Velocities, Underwater Atomic 

Burst, 20 P 

Authors: Gibson T.A. Jr. 

Publication date: 195203 

Report Numbers: AFSWP 0155 

e. Item number: DNA 6034 

Title: Operation GREENHOUSE 1951 (U), 334 P. 

Authors: Berkhouse L. ; Davis S.E. ; Gladeck F.R. ; Hallowell J.H. ; Jones C.B. ; Martin E.J. ; 

McMullan F.W. ; Osborne M.J. 

Corporate Authors: DASIAC (SANTA BARBARA, CA) 

Publication date: 198306 

Report Numbers: DNA 6034F ; KT 82 046(F) 

f. Item number: XRD 185 

Title: Operation Crossroads; Radiological Decontamination of Target And Non-Target Vessels; 

Vol. 1, 145 P 

Authors: Fee J.J. 

Corporate Authors: Navy/Director Of Ship Material 

Publication date: 4906 

Report Numbers: XRD 185 

Enclosure (3) 
REVIEW OF NIOSH’s SEC PETITION EVALUATION REPORT
 

PETITION SEC-00020
 

David C. Kocher
 

SENES Oak Ridge, Inc.
 

Oak Ridge, Tennessee
 

Introduction 

I have reviewed the evaluation report of the National Institute for Occupational Safety 

and Health (NIOSH) that covers a class of employees proposed for addition to the Special 

Exposure Cohort (SEC) under the Energy Employees Occupational Illness Compensation 

Program Act (EEIOCPA) of 2000 and applicable regulations in 42 CFR Part 83. The NIOSH 

evaluation report, which was issued on October 20, 2005, in response to Petition SEC-00020, 

covers all employees of the Department of Energy (DOE), DOE contractors, or subcontractors 

that were employed at the Pacific Proving Ground (PPG) from 1946 through 1962. 

My perspective in reviewing the NIOSH evaluation report is the following. First, I take 

no position on the question of whether energy workers at the PPG should be granted SEC status 

under the EEIOCPA. I am concerned only with NIOSH’s technical justifications for its 

conclusion that SEC status should be granted. 

Second, my review is greatly influenced by my role as a member of the committee of the 

National Research Council (NRC) that prepared the 2003 report on “A Review of the Dose 

Reconstruction Program of the Defense Threat Reduction Agency.” In concluding that energy 

workers at the PPG should be granted SEC status, NIOSH relied heavily on findings in the NRC 

report concerning deficiencies in methods of dose reconstruction for atomic veterans used by the 

Defense Threat Reduction Agency (DTRA) in the Nuclear Test Personnel Review (NTPR) 

Program, especially methods of estimating dose from inhalation of radionuclides. Thus, I have a 

strong personal and professional interest in whether the NIOSH evaluation report discusses 

findings in the NRC report in a fair and balanced manner, and my review of the evaluation report 

focuses mainly on Section 7.1 on NTPR Dose Reconstructions. 

Discussion of Principal Concerns 

Based upon my review of Section 7.1 of the NIOSH evaluation report and my intimate 

familiarity with discussions and analyses in the 2003 NRC report, I am forced to conclude that 

the evaluation report does not present a fair and balanced discussion of findings in the NRC 

report on deficiencies in methods of estimating internal doses, especially inhalation doses, in the 

NTPR Program. Indeed, in some important respects, I believe that discussions in the evaluation 

report present a highly distorted and misleading view of findings in the NRC report. My 

concerns about Section 7.1 of the evaluation report center on two points, as described below. 

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Presentation of Findings in 2003 NRC Report 

[1] My first major concern about Section 7.1 of the evaluation report involves a discussion in 

the section on Internal Dose Issues that begins on page 11. The second paragraph starts by 

noting, correctly, that “[t]he NRC review raised a number of issues associated with the methods 

used by DTRA to estimate inhalation dose.” The discussion then notes, again correctly, that 

those issues are summarized in two tables in the NRC report, one of which “identified issues that 

potentially overestimated internal doses” (i.e., assumptions that should tend to result in 

overestimates of inhalation dose to atomic veterans). However, the evaluation report then states 

that “[t]hese issues were not evaluated in this SEC evaluation” (emphasis mine). Following 

this statement is a presentation and discussion of the second table in the NRC report, which 

summarizes findings on ways in which methods of dose reconstruction for atomic veterans could 

result in substantial underestimates of credible upper bounds (at least upper 95% credibility 

limits) of inhalation doses. It is those findings that are used in the evaluation report to support 

NIOSH’s conclusion that energy workers at the PPG should be granted SEC status. 

In my opinion, the approach in the NIOSH evaluation report of presenting only those 

findings in the NRC report that address deficiencies in methods used in the NTPR Program to 

estimate upper bounds of inhalation doses to atomic veterans, while ignoring other findings 

concerning assumptions used in dose reconstructions for atomic veterans that should tend to 

overestimate inhalation doses, is unfair and unbalanced, with the result that the NRC report is 

misrepresented in important ways. I expected that NIOSH’s evaluation of findings in the NRC 

report would be based on a less biased presentation of those findings. 

My criticism is not meant to imply that an unbiased evaluation of the NRC report would 

not support NIOSH’s conclusion that the SEC petition should be granted. The NRC report did 

identify many issues with methods of estimating internal dose to atomic veterans, and some of 

those issues have not been fully resolved. However, a balanced discussion of findings in the 

NRC report concerning methods of estimating inhalation dose to atomic veterans, which I 

believe is important, would have acknowledged and taken into account the following:

 •	 discussions in Section V.C.3.1 of the NRC report on assumptions that should tend to 

overestimate inhalation dose, as summarized in Table V.C.5, which parallel discussions 

in Section V.C.3.2 on assumptions with substantial uncertainty that is not taken into 

account or assumptions that should tend to underestimate inhalation dose, as summarized 

in Table V.C.7 and reproduced on page 12 of the evaluation report;

 •	 discussions in Section V.C.3.3 that present the NRC committee’s evaluation of methods 

of estimating inhalation dose to atomic veterans, which is summarized below;

 •	 discussions in Section V.C.5 that summarize the principal findings related to methods of 

estimating internal dose and attempt to provide an overall perspective on those findings; 

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 •	 discussions in Section V.C.6 that present conclusions on the credibility of estimated 

upper bounds of inhalation dose to atomic veterans; and

 •	 discussions in Section VI.C which emphasize that methods used in the NTPR Program to 

estimate inhalation dose on the basis of estimates of external exposure rates due to 

radionuclides in fallout deposited on the ground are valid as long as assumed exposure 

scenarios are reasonable representations of conditions of exposure of atomic veterans. 

Discussions in Section V.C.3.3 of the NRC report are particularly relevant to the NIOSH 

evaluation report, in my opinion. Those discussions consider all the favorable findings on 

methods of estimating inhalation dose, as summarized in Tables V.C.5, and all the unfavorable 

findings, as summarized in Table V.C.7, and attempt to address the question of whether, on the 

whole, methods used in the NTPR Program to estimate inhalation doses to atomic veterans 

provide credible upper bounds. The NRC report indicates that this question is difficult to answer 

in general terms, but that certain conclusions about the credibility of estimated upper bounds of 

inhalation dose in particular exposure scenarios appear to be warranted. 

Section V.C.3.3 of the NRC report noted that a scenario in which credible upper bounds 

of inhalation dose to atomic veterans probably are obtained involves exposure to descending 

fallout throughout the period of descent on residence islands at the PPG. This scenario is 

particularly relevant to exposures of NIOSH’s cohort of energy workers at the PPG. The NRC 

report also noted that there are clear examples of scenarios in which estimated inhalation doses 

to atomic veterans are not credible upper bounds. However, those scenarios occur at the Nevada 

Test Site (NTS) and are not directly relevant to exposures at the PPG. Finally, the NRC report 

considered scenarios that involved inhalation of previously deposited fallout that was 

resuspended by such disturbances as walking or light vehicular traffic. Such scenarios were 

common at the PPG. The NRC report concluded that assumptions used in dose reconstructions 

for atomic veterans more likely than not overestimate actual doses in the assumed resuspension 

scenarios. Although the NRC committee could not determine whether estimated inhalation 

doses in those scenarios are credible upper bounds, discussions and analyses in the NRC report 

indicate that it is highly unlikely that estimated doses are far below credible upper bounds (e.g., 

that credible upper bounds could be higher by an order of magnitude or more). 

[2] My second major concern about Section 7.1 of the evaluation report involves the first 

sentence in the Conclusion section at the top of page 14. This sentence begins as follows (again, 

emphasis mine): “Based on issues identified by the NRC that questioned the ability to establish 

an upper bound dose reconstruction, NIOSH has determined ...” A similar statement appears 

on page 13 in the second sentence of the paragraph immediately preceding the section on 

External Dose Issues. I believe that both statements are highly objectionable, essentially because 

they basically misrepresent findings in the NRC report. Such a conclusion does not even follow 

from the biased discussion of the NRC report’s findings on methods of estimating inhalation 

dose to atomic veterans, as discussed above. 

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I can say with great confidence that there is not a single discussion in the NRC report that 

indicates or implies that credible upper bounds of internal doses to atomic veterans cannot be 

established, i.e., that there is no “ability” to establish credible upper bounds on the basis of 

available data and reasonable assumptions about exposure scenarios. Rather, the NRC report is 

concerned only with the question of whether estimated upper bounds of doses to atomic veterans 

are credible, which is a very different issue from the one implied by the statements in the 

evaluation report noted above. A 2000 report to Congress by the General Accounting Office 

(GAO) noted in the evaluation report had concluded that dose reconstruction is a valid method of 

estimating doses to atomic veterans for purposes of adjudicating claims for compensation, and 

nothing in the NRC report contradicts or questions that conclusion. 

Role of 2003 Interim Guidance 

In justifying its conclusion that energy workers at the PPG should be granted SEC status, 

the NIOSH evaluation report noted that a 2004 report to Congress from the Department of 

Defense presented several plans of action to correct deficiencies in DTRA’s dose reconstruction 

program that were identified in the NRC report. The evaluation report also noted, correctly, that 

some issues discussed in the NRC report and the report to Congress have not been fully resolved 

for incorporation in methods of dose reconstruction for atomic veterans. 

However, I was surprised that the NIOSH evaluation report did not mention the Interim 

Guidance that was issued by DTRA on July 16, 2003, in response to the NRC report. The 

Interim Guidance specified improvements to the dose reconstruction process for atomic veterans 

to be implemented immediately. Certain findings in the NRC report on methods of dose 

reconstruction were addressed by specifying simple adjustment factors to be applied to estimated 

doses as a means of obtaining more credible upper bounds. For example, the adjustment factor 

of 10 to be applied to estimates of inhalation dose in most scenarios was intended to address 

important deficiencies in methods of estimating inhalation dose identified in the NRC report. 

NIOSH may have been unaware of DTRA’s Interim Guidance. However, given the 

importance of the Interim Guidance to current methods of dose reconstruction in the NTPR 

Program, I believe that discussions of the NTPR Program in Section 7.1 of the evaluation report 

need to take the Interim Guidance into account. 

Other Comments on NIOSH Evaluation Report 

Additional comments on the NIOSH evaluation report are given below. Some of these 

comments provide additional discussion of the more general concerns described above. 

[1] The evaluation report often uses the term “sufficient accuracy” to describe how NIOSH 

must be able to estimate doses (e.g., see page 4, first paragraph of Section 2.0). However, I did 

not find what I would consider to be a satisfactory discussion of what “sufficient accuracy” 

means, especially since upper credibility limits of dose are of primary importance in the 

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compensation program for energy workers, not best estimates. The “accuracy” of an estimated 

dose doesn’t matter much as long as an assumed uncertainty or bias in that estimate is credible. 

[2] On page 6, a statement at the end of the paragraph immediately preceding Section 4.2 

notes that dose reconstructions have been completed for three claims for compensation by energy 

workers at the PPG. Given NIOSH’s conclusion that inhalation doses to those workers cannot 

be estimated reliably at the present time, I think it would be of interest to discuss how doses to 

the three claimants were estimated (e.g., how difficulties in estimating dose were addressed). 

[3] On page 7, the first row in Table 5.1 notes that there have been reports of defective seals 

in film badges used at Operation DOMINIC I. This table might also note that there are concerns 

about damaged film at other operations in the Pacific, including Operation REDWING. The 

NRC report provides discussions on this issue. 

[4] The 2000 GAO report to Congress, which led to the 2003 NRC report, is mentioned in 

the second paragraph of Section 7.1 on page 11. However, in the interest of fairness and 

accuracy, I believe that the NIOSH evaluation report should mention the GAO report’s 

conclusion that dose reconstruction is a valid method of estimating doses to atomic veterans for 

purposes of adjudicating claims for compensation. I also noticed that the GAO report is not 

included in the reference list beginning on page 19. 

[5] If Table V.C.7 from the NRC report, as given on page 12 of the evaluation report, is 

retained, I believe that the evaluation report should note that some of the points in that table 

apply only at the NTS and, thus, are not relevant to dose reconstructions at the PPG. 

[6] On page 12, the statement immediately following Table V.C.7 from the NRC report is 

correct. However, as discussed in a previous comment, that statement probably is misleading in 

regard to dose reconstructions at the PPG, where concerns about obtaining credible upper bounds 

of inhalation dose to atomic veterans appear to be less important. 

[7] The beginning of the last paragraph on page 12 notes that “[m]ost of the issues dealing 

with uncertainty are similar to issues NIOSH has already or is currently dealing with ...” I think 

it would be helpful to be more explicit about particular issues that are similar in the two 

programs. That statement also begs the question of why NIOSH believes that it isn’t able to deal 

with those issues at the PPG when they are dealing with them in other cases. 

[8] In regard to the last paragraph of the section on External Dose Issues on page 13, I would 

argue that the approach of applying uncertainty factors to ensure that reasonable estimates of 

external dose are obtained, which NIOSH expects to use in its dose reconstructions, also can be 

applied in estimating internal dose. Indeed, just such an approach is specified in DTRA’s 2003 

Interim Guidance, as noted in a previous comment. 

[9] I do not object to discussions in the section on Ingestion on page 15. However, I do think 

that an important implication of analyses of ingestion scenarios in the NRC report is that 

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reasonable bounding estimates of ingestion dose can be obtained for use in dose reconstructions 

for specific individuals. This point perhaps deserves greater emphasis. 

[10] In the section on Neutrons on page 16, there are two statements that, if I understand 

them, don’t seem right. The first is a statement that, in addition to detonation events, a potential 

source of neutron exposure is “accessing the detonation locations for recovery of monitoring 

equipment.” A later sentence then refers to access controls that were implemented “following 

the detonations,” as if this had something to do with controlling exposures to neutrons. I don’t 

know what the authors of this section intended (and the summary of neutron dosimetry data in 

Table 5.1 on page 7 does not help me), but the fact of the matter is that all exposures to neutrons 

occurred essentially at the time of detonation (or within a few seconds after a detonation, as 

short-lived fission products that are delayed neutron emitters decayed), and exposures to 

neutrons did not occur during post-detonation recovery of monitoring equipment. 

I would also note that although NIOSH did not complete an evaluation of the feasibility 

of estimating neutron doses, such doses can be estimated, in the rare instances when they 

occurred at the PPG, on the basis of information given in reports issued by the NTPR Program. 

[11] Section 7.3 on Occupational Medical Exposures on page 16 interested me in the 

following way. This section basically argues that doses from occupational medical exposures of 

energy workers at the PPG can be estimated even in the absence of directly relevant data. I do 

not take issue with that conclusion; indeed, I believe that the approach to estimating dose 

outlined there is reasonable. However, in the interest of fairness, I believe that NIOSH should 

acknowledge that simple approximations based on available data also can be used in estimating 

internal dose, when this is indeed the case. 

[12] As in previous comments, I believe that the statement at the end of the third paragraph on 

page 17 about “the lack of reliable information to establish plausible maximum limits to this 

exposure” is highly misleading. Again, the concern here, as I see it, is the crucial difference 

between establishing the degree of reliability of models and data (i.e., the magnitude of 

uncertainties or biases), which is an issue that has not been fully resolved in dose reconstructions 

for atomic veterans, and an inability to establish the reliability of models and data, which is not 

an issue when data do exist that can be used to establish reliability. 

Summary 

I believe that NIOSH’s evaluation report on the SEC petition for energy workers at the 

PPG should be revised with two important goals in mind:

 (1) The evaluation report should present a fair and balanced discussion of findings in the 

2003 NRC report on the adequacy of methods of dose reconstruction for atomic veterans 

used in the NTPR Program, especially methods of estimating inhalation dose, and the 

implications of those findings for dose reconstructions for energy workers at the PPG. 

The evaluation report also should discuss DTRA’s 2003 Interim Guidance, which was 

6
 
issued in response to the NRC report, and its importance in improving the credibility of 

estimated upper bounds of doses to atomic veterans.

 (2) The evaluation report should not contain any statements that imply that methods of dose 

reconstruction used in the NTPR Program are invalid. Discussions and analyses in the 

2003 NRC report do not support any such conclusion. Indeed, I believe that NIOSH 

should acknowledge explicitly that the validity of methods of dose reconstruction used in 

the NTPR Program is not at issue, even though some uncertainties or biases in estimates 

of dose to atomic veterans obtained using those methods have not been fully assessed. 

I also believe that a fair and balanced discussion of findings in the 2003 NRC report, 

combined with a finding by NIOSH that potentially important issues identified in the NRC report 

and the 2004 report to Congress have not been fully resolved, could still support NIOSH’s 

conclusion that energy workers at the PPG should be granted SEC status. However, as noted 

previously, I take no position on whether SEC status should be granted. My only concern is that 

NIOSH’s arguments should be sound and defensible. 

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