b. internal doses for workers involved in plutonium operations when
plutonium was enriched with the calutrons.

Health Endangerment

The Secretary established the health endangerment determination for the class of
employees covered by this report 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 the finding of NIOSH 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).

Vv. — Effect and Effective Date of Designation

The Secretary submits this report on designation of one additional class to the SEC
for review by Congress, pursuant to 42 U.S.C. §§ 7384/(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. § 7384/(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.

HHS Special Exposure Cohort Designation:
Y-12 Plant, Oak Ridge. Tennessee


HHS Designation of Additional Members of the
Special Exposure Cohort

under the
Energy Employees Occupational Illness Compensation Program Act

Designating a Class of Employees from

Y-12 Plant
Oak Ridge, Tennessee

HHS Special Exposure Cohort Designation:
Y-12 Plant, Oak Ridge, Tennessee


1. Designation

I, Michael O. Leavitt, Secretary of Health and Human Services (“the Secretary’),
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.

AUG - 8 2006 .
\

Date Michael O. Leavitt

II. | Employee Class Definition

Department of Energy (DOE) employees or DOE contractor or subcontractor
employees who were monitored or should have been monitored for:

(1) thorium exposures while working in Building 9201-3, 9202, 9204-1, 9204-3.
9206, or 9212 at Y-12 for a number of work days aggregating at least 250
work days from January 1948 through December 1957 or in combination with
work days within the parameters (excluding aggregate work day
requirements) established for one or more classes of employees in the SEC: or

(2) radionuclide exposures associated with cyclotron operations in Building 9201-
2 at Y-12 for a number of work days aggregating at Jeast 250 work days from
January 1948 through December 1957 or in combination with work days
within the parameters (excluding aggregate work day requirements)
established for one or more classes of employees in the SEC.

Ill. Designation Criteria and Recommendations

Pursuant to 42 U.S.C. § 73844, for the class defined in Section II of this report, the
Secretary has determined, and the Advisory Board on Radiation and Worker Health
(“the 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

HHS Special Exposure Cohort Designation:
Y-12 Plant, Oak Ridge, Tennessee


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 dated July 5, 2006 and received by the
Secretary on July 6. 2006.

IV. Designation Findings

Feasibility of Estimating Radiation Doses with Sufficient Accuracy

The Secretary established the feasibility determination for the class of employces
covered by this report upon the findings summarized below.

(1) There are insufficient bioassay or air sampling data to reconstruct internal thorium
dose for employees who worked from January 1948 through December 1957 in
buildings where thorium operations took place: buildings 9201-3, 9202, 9204-1,
9204-3, 9206, and 9212.

(2) There are insufficient bioassay or air sampling data to reconstruct internal dose
for cyclotron workers (employees who worked in Building 9201-2) from January
1948 through December 1957. These workers may have accumulated substantial
chronic exposures through episodic intakes of a variety of radionuclides that were
produced during the cyclotron operation period.

(3) Pursuant to 42 C.F.R. § 83.13(c)(1), NIOSH determined that there is insufficient
information either 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, or to estimate the
radiation doses of members of the class more precisely than a maximum dose
estimate.

(4) NIOSH determined that it is possible to reconstruct or bound occupationally
required medical doses and external gamma, beta, and neutron doses. NIOSH
also found that sufficient bioassay data from January 1948 through December
1957 are available for reconstruction of:

a. internal doses for workers with potential for exposure to uranium or
recycled uranium contaminants (plutoinium-238 (plutonium-239 in lesser
quantities), neptunium-237, and technetium-99); and

HHS Special Exposure Cohort Designation:
Y-12 Plant, Oak Ridge, Tennessee