HHS Special Exposure Cohort Designation:

St. Louis Airport Storage Site, St. Louis, Missouri

 

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 

St. Louis Airport Storage Site

St. Louis, Missouri 
HHS Special Exposure Cohort Designation:

St. Louis Airport Storage Site, St. Louis, Missouri

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.

____July 14, 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 in any area and in any job 

capacity at the St. Louis Airport Storage Site in St. Louis, Missouri, from 

January 3, 1947 through November 2, 1971, 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 Special 

Exposure Cohort. 

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 June 16, 

2010.
HHS Special Exposure Cohort Designation:

St. Louis Airport Storage Site, St. Louis, Missouri

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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 of workers at the St. Louis Airport 

Storage Site (SLASS) may have received internal radiation exposures from the 

inhalation and ingestion of uranium and uranium progeny particulates, and the 

inhalation of radon. NIOSH also determined that members of this class may 

have received external radiation exposures from uranium daughters, primarily 

radium226, present during operations at the site. 

• NIOSH found that the available monitoring records, process descriptions, and 

source-term data are not adequate to calculate the internal dose with sufficient 

accuracy for the period from January 3, 1947 through November 2, 1971. During 

this time, there were many tons of raffinate residues in storage piles without 

cover or controls to protect personnel from internal exposures. These residues 

contained uranium and uranium progeny in disequilibrium that were not 

sufficiently radiologically characterized. Workers were not adequately monitored 

for internal exposure to these materials. Consequently, NIOSH lacks sufficient 

information, which includes biological monitoring data, sufficient air monitoring 

information, or sufficient process and radiological source information, to allow it 

to estimate with sufficient accuracy the potential internal exposures to various 

radionuclides to which the proposed class may have been subjected.

• NIOSH found that the available monitoring records, process descriptions, and 

source-term data are adequate to complete dose reconstructions with sufficient 

accuracy for the period from November 3, 1971 through December 31, 1973 and 

from January 1, 1984 through December 31, 1998. Consequently NIOSH finds 

that it is not feasible to estimate, with sufficient accuracy, the total internal dose 

for workers at SLASS during the period from January 3, 1947 through November 

2, 1971.

• 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.

• NIOSH believes that external photon exposure may be bound for the period from 

January 3, 1947 through November 2, 1971, using guidance from the document, 

Basis for Development of an Exposure Matrix for the Mallinckrodt Chemical 

Company St. Louis Downtown Site and the St. Louis Airport Site, St. Louis, 

Missouri (ORAUT-TKBS-0005). 
HHS Special Exposure Cohort Designation:

St. Louis Airport Storage Site, St. Louis, Missouri

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

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

monitoring data that may become available for an individual claim (and that can 

be interpreted using existing NIOSH dose reconstruction processes or 

procedures). Therefore, dose reconstructions for individuals employed at the St. 

Louis Airport Storage Site during the period from January 3, 1947 through 

November 2, 1971, but who do not qualify for inclusion in the Special Exposure 

Cohort, may be performed using these data as appropriate.

• NIOSH finds that reconstruction of medical dose is likely to be feasible by using 

claimant-favorable assumptions in the Technical Information Bulletin, Dose 

Reconstruction from Occupationally Related Diagnostic X-Ray Procedures

(ORAUT-OTIB-0006).

• 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:

St. Louis Airport Storage Site, St. Louis, Missouri

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IV. 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.”

V. 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.