U.S. Department of Labor Employment Standards Adr
Office of Workers’ Comps

Illness Compe:
Washington, D.C

WL 29

Mr. Larry J. Elliott

Director, Office of Compensation Analysis and Support
National Institute for Occupational Safety and Health
Centers for Disease Control and Prevention

Mail Stop C-46

4676 Columbia Parkway

Cincinnati, Ohio 45226

Re: Return of Iowa Army Ammunition Plant Cases for New SEC Class for 1949 - 1974
Dear Larry:

On May 20, 2005, the Secretary of Health and Human Services, designated the following
class for addition to the Special Exposure Cohort (SEC) in a report to Congress:

Employees of the Department of Energy (DOE) or DOE contractors or
subcontractors employed by the lowa Army Ammunition Plant, Line 1,
during the period from March 1949 through 1974 and who were employed
for a number of work days aggregating at least 250 work days either solely
under this employment or in combination with work days within the
parameters (excluding aggregate work day requirements) established for
other classes of employees included in the SEC.

This designation became effective on June 20, 2005, as provided for under 42 U.S.C.
73841(14)(C). Hence, beginning on June 20, 2005, members of this class of employees,
defined as reported in this notice, became members of the SEC.

A report attached to Secretary Leavitt’s letter entitled “HHS Designation of Additional
Members of the Special Exposure Cohort” provided the supporting rationale for
designating a class of employees from the lowa Army Ammunition Plant, Line 1, for the
period from March 1949 through 1974. That report stated that the Secretary of Health
and Human Services has determined in regard to the above reference class that it is not
feasible to estimate with sufficient accuracy the radiation dose that the class received.

Section IV, “Designation Findings,” of the report for the March 1949 through 1974
period summarized his findings on this issue as follows.

(1) NIOSH determined that, “... it lacks access to sufficient information
to either 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 with sufficient accuracy.”

(2) “The ‘work factor’ evaluation initially proposed by NIOSH as a
means of doing dose reconstruction for the period March 1949 - December
1962 is based, in part, on the assumption that workers who handled the
pits did so for up to one hour per shift. Former workers at the lowa Army
Ammunition Plant (IAAP) offered credible statements that they handled
pits during the period on question for significantly more than one hour per
shift.”

(3) “For the period January 1963 — December 1974, NIOSH has personal
monitoring data that could be used to estimate radiation exposures at the
IAAP. However, the Board in its deliberations found that it could not
verify the representativeness of these data for use in assessing radiation
exposures at the IAAP. In addition, personal exposures in some job
categories with significant radiation exposures were never monitored.”

(4) “For the period from 1957 to 1974, Line 1 employees at IAAP who
worked in the “gravel gerties” were “... likely to have been exposed to
naturally occurring radon and its progeny that could have been
concentrated subsequently by the design and ventilation characteristics of
these unique constructions.” It was determined that “... it was not feasible
to estimate the maximum radiation dose to which employees of Line 1 of
IAAP who worked in the gravel gerties might have been exposed from
naturally occurring radon, or to estimate these doses more precisely.”

(5) NIOSH proposed to use different methods for calculating dose, i.e.,
models for the period March 1949 — December 1962, and personnel
monitoring data for the period January 1963 — December 1974. Using
these two methods, the annual median external photon and neutron
external doses for the two periods differed by more than a factor of ten.
The Board concluded, and NIOSH concurs, that this significant difference
demonstrates that NIOSH cannot estimate dose during this period with
sufficient accuracy.”

In that report, the Secretary of Health and Human Services has determined that it is not
feasible to undertake dose reconstructions for the class of employees employed at Iowa
Army Ammunition Plant, Line 1, for the period from March 1949 through 1974 based
upon the site profile prepared by the National Institute for Occupational Safety and
Health (NIOSH). Thus, it appears that the only dose reconstructions that can be
completed for members of the designated class are dose reconstructions based upon
actual measured exposure of the individual worker whose dose is being reconstructed.

Accordingly, NIOSH should return all cases in which the employee involved has been
determined by the Department of Labor (DOL) to have sustained a specified cancer to


the DOL Denver District Office for the Office of Workers’ Compensation Programs to
complete adjudication as appropriate. NIOSH should also notify these claimants that
their case has been returned to DOL for adjudication as an SEC cancer.

For any cases in which DOL has determined that the employee involved sustained only
non-specified cancer(s), NIOSH should determine whether it has obtained (or can obtain)
any actual exposure data for that employee. If it has not obtained (or cannot obtain) any
actual exposure data for that employee, it should inform the claimant(s) that as a result of
the determination by the Secretary of HHS concerning the Iowa Army Ammunition Plan
Special Exposure Cohort petition, NIOSH is only able to perform dose reconstruction in
regard to their claim based upon actual exposure data of the employee involved in the
claim, that no such data has been located and that, as a result, dose reconstruction is not
feasible for their case and it has been returned to DOL for adjudication.

If NIOSH does locate actual exposure data for an employee who has been determined by
DOL to have sustained only non-specified cancer(s), NIOSH should complete a dose
reconstruction based only upon that data. The dose reconstruction report sent to
claimant(s) in such cases should explain that as a result of the determination by the
Secretary of HHS concerning the lowa Army Ammunition Plan Special Exposure Cohort
petition, NIOSH is only able to perform dose reconstruction in regard to their claim based
upon actual exposure data for the employee involved in the claim, and that NIOSH
cannot make use of other estimation techniques discussed in the Site Profile. The
claimant(s) should be informed that the dose reconstruction report is thus based only on
the individual exposure data NIOSH had obtained.

If you could forward us drafts of the letter to be sent to claimants where NIOSH finds it
not feasible to perform a dose reconstruction because of the lack of any actual exposure
data and of the explanation to claimants to be included in the dose reconstruction report
to explain that dose reconstruction was limited to actual exposure data, we can ensure
that our explanation of the process is consistent with that of NIOSH.

Sincerely,

Cc > —
\te. YF laerte
Peter M. Turcic

Director, Division of Energy Employees
Occupational IIIness Compensation