HHS Special Exposure Cohort Designation:

Nevada Test Site, Mercury, Nevada

 

HHS Designation of Additional Members of the 

Special Exposure Cohort 

under the 

Energy Employees Occupational Illness Compensation Program Act of 2000 

Designating a Class of Employees from 

Nevada Test Site 

Mercury, Nevada
HHS Special Exposure Cohort Designation:

Nevada Test Site, Mercury, Nevada

Page 2

I. Designation 

I, Kathleen Sebelius, Secretary of Health and Human Services, designate the class 

of employees defined in Section II of this report for addition to the Special Exposure 

Cohort (SEC), as authorized under the Energy Employees Occupational Illness

Compensation Program Act of 2000 (EEOICPA), 42 U.S.C. § 7384q.

 _April 5, 2010________ __[Signature on file]_______

Date Kathleen Sebelius

II. Employee Class Definition

All employees of the Department of Energy, its predecessor agencies, and its 

contractors and subcontractors who worked at the Nevada Test Site, from 

January 1, 1963 through December 31, 1992, for a number of work days 

aggregating at least 250 work days, occurring either solely under this 

employment or in combination with work days within the parameters 

established for one or more other classes of employees in the SEC. 

III. Designation Criteria and Recommendations

Pursuant to 42 U.S.C. § 7384q, for the class defined in Section II of this report, the 

Secretary has determined, and the Advisory Board on Radiation and Worker Health 

(Board) has recommended, that

(1) it is not feasible to estimate with sufficient accuracy the radiation dose that the 

class received; and

(2) there is a reasonable likelihood that such radiation dose may have 

endangered the health of members of the class.

The SEC final rule states in 42 C.F.R. § 83.13(c)(1) that it is feasible in two situations 

to estimate the radiation dose that the class received with sufficient accuracy. First, 

the rule states that radiation doses may be estimated with sufficient accuracy if 

NIOSH has established that it has access to sufficient information to estimate the 

maximum radiation dose for every type of cancer for which radiation doses are 

reconstructed that could have been incurred under plausible circumstances by any 

member of the class. Alternatively, radiation doses may be estimated with sufficient 

accuracy if NIOSH has established that it has access to sufficient information to 

estimate the radiation doses of members of the class more precisely than a 

maximum dose estimate.

The Board, pursuant to 42 U.S.C. § 7384q, advised the Secretary to designate the 

class as an addition to the SEC in a letter received by the Secretary on March 8, 

2010. 
HHS Special Exposure Cohort Designation:

Nevada Test Site, Mercury, Nevada

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IV. Designation Findings

Feasibility of Estimating Radiation Doses with Sufficient Accuracy

The Secretary established the feasibility determination for the class of employees 

covered by this report based upon the findings summarized below.

• NIOSH determined that members of this class may have received internal and

external radiation exposures from a variety of radionuclides that may have been 

present during various operations at the site. 

• NIOSH has identified exposure scenarios involving varying job titles/duties and 

work activities, such as drill-backs, post-test work activities, and construction or 

other soil-disturbing activities in areas that had been contaminated by previous 

tests. While a large number of radiological technicians and security personnel 

were routinely sampled for bioassay at NTS, a substantial fraction of other job 

titles/duties group of bioassay samples appear to have been collected on a more 

event or incident-driven basis. Prior to 1993, NIOSH has not been able to locate 

sufficient documented evidence, other than anecdotal information, to describe a 

consistent rationale behind the collection of personnel bioassay samples or to 

indicate that sampling occurred consistently in the situations where it was 

required. Because of this, NIOSH cannot conclusively determine that doses to all 

of these potentially-exposed individuals were detected by the bioassay program. 

• NIOSH has identified data gaps that exist in the electronically-available bioassay 

data for certain radionuclides and time periods. 

• Because of the episodic nature of NTS exposures, a co-worker model that is 

useful in reconstructing chronic intake scenarios would not necessarily be 

representative of the exposure patterns of the NTS workforce. 

• The reconstruction of NTS internal doses is also complicated by the variety of the 

radionuclides to which workers may have been exposed. As indicated in the NTS 

Site Profile, the potential radionuclide source term included (but is not limited to): 

plutonium, americium, uranium, thorium, radium, iodine, and other fission 

products. For workers with no bioassay records, and who had the potential for 

exposure, NIOSH would have to definitively establish the relative mixture of the 

exposure source term. 

• NIOSH lacks sufficient information, which includes specific biological monitoring 

data, sufficient air monitoring information, sufficient process and radiological 

source information, that would allow it to estimate the potential internal 

exposures to various radionuclides to which the proposed class may have been 

subject at NTS during the period from January 1, 1963 through December 31, 

1992. 

• Although NIOSH found that it is not possible to completely reconstruct internal 

radiation doses for the proposed class, NIOSH intends to use any internal and 

external monitoring data that may be available for an individual claim (and that 

can be interpreted using existing NIOSH dose reconstruction processes or 
HHS Special Exposure Cohort Designation:

Nevada Test Site, Mercury, Nevada

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procedures). Therefore, dose reconstructions for individuals employed at NTS 

during the period from January 1, 1963 through December 31, 1992, but who do 

not qualify for inclusion in the SEC, may be performed using these data as 

appropriate. 

• NIOSH has access to sufficient personnel monitoring and workplace monitoring 

data to reconstruct external exposures for all monitored workers. 

• NIOSH does believe it is possible to reconstruct with sufficient accuracy all 

external and occupational medical X-ray dose for the evaluated period. 

• Pursuant to 42 C.F.R. § 83.13(c)(1), NIOSH determined that there is insufficient 

information to either: (1) estimate the maximum radiation dose, for every type of 

cancer for which radiation doses are reconstructed, that could have been 

incurred under plausible circumstances by any member of the class; or (2) 

estimate the radiation doses of members of the class more precisely than a 

maximum dose estimate.

• The Board concurred with the NIOSH evaluation and recommended the proposed

class for addition to the SEC.

 Health Endangerment

The Secretary established the health endangerment determination for the class of 

employees covered by this report based upon the findings summarized below.

(1) Pursuant to 42 C.F.R. § 83.13(c)(3), NIOSH established that there is a 

reasonable likelihood that such radiation doses may have endangered the 

health of members of the class. Pursuant to 42 C.F.R. § 83.13(c)(3)(ii), 

NIOSH specified a minimum duration of employment to satisfy this health 

endangerment criterion as “having been employed for a number of work days 

aggregating at least 250 work days within the parameters established for this 

class or in combination with work days within the parameters (excluding 

aggregate work day requirements) established for one or more other classes 

of employees in the Cohort.”

(2) NIOSH did not identify any evidence from the petitioners or from other 

resources that would establish that the class was exposed to radiation during 

a discrete incident likely to have involved exceptionally high-level exposures, 

such as a nuclear criticality incident, as defined under 42 C.F.R. § 

83.13(c)(3)(i). 

(3) The Board concurred with NIOSH’s finding that the health of the class may 

have been endangered and defined the class according to the 250-work day 

requirement specified under 42 C.F.R. § 83.13(c)(3)(ii). 
HHS Special Exposure Cohort Designation:

Nevada Test Site, Mercury, Nevada

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V. Effect and Effective Date of Designation

The Secretary submits this report on the designation of one additional class to the 

SEC for review by Congress, pursuant to 42 U.S.C. §§ 7384l(14)(C)(ii) and 

7384q(c)(2)(A), as amended by the Ronald W. Reagan National Defense 

Authorization Act for Fiscal Year 2005, Pub. L. No. 108-375 (codified as amended in 

scattered sections of 42 U.S.C.). Pursuant to 42 U.S.C. § 7384l(14)(C)(ii), as 

amended by the Ronald W. Reagan National Defense Authorization Act for Fiscal 

Year 2005, Pub. L. No. 108-375 (codified as amended in scattered sections of 42 

U.S.C.), the designation in this report will become effective 30 days after the date of 

this report’s submission to Congress “unless Congress otherwise provides.”

VI. Administrative Review of Designation

The health endangerment determination of the designation provided in this report 

may be subject to an administrative review within HHS, pursuant to 42 C.F.R. § 

83.18(a). On the basis of such a review, if the Secretary decides to expand the class 

of employees covered by this designation, the Secretary would transmit a 

supplementary report to Congress providing the expanded employee class definition 

and the criteria and findings on which the decision was based.