United Nuclear Corp.

(Site Profile/Docket Number 170)

Location: Hematite, Missouri

Also known as: Mallinckrodt Chemical Works, Chemicals Div.

Special Exposure Cohort Petition Information

The Special Exposure Cohort (SEC) is a unique category of employees established by the Act (42 CFR Part 83). Claims compensated under the SEC do not have to go through the dose reconstruction process. To qualify for compensation under the SEC, a covered employee must meet specific requirements (e.g., must have at least one of 22 “specified cancers,” and have worked for a specified time period at one of the SEC sites). Classes of employees and work sites can be considered for addition to the SEC through a NIOSH petition process. More information about the Special Exposure Cohort can be found on our Frequently Asked Questions page.

Open/Active SEC Petitions

There are currently no open/active petitions from United Nuclear Corp.

Classes Not Added to the SEC

  • All site employees who worked in any area of the United Nuclear Corporation— Hematite, Missouri, site from January 1, 1958, through December 31, 1973, and the residual period January 1, 1974, through July 31, 2006.

    Note: This class was established from Petition 116

Petitions Qualified for Evaluation

Below is a list of the petitions that qualified for evaluation. Select a petition on the list to view the table for that particular petition.

Petition 116
Steps in Petition Process: Petition Details:

Date Received

June 19, 2008

Date Qualified for Evaluation

November 4, 2008

Summary of Information in Petition

Job Titles and/or Job Duties: All site employees

Period of Employment: January 1, 1958 through December 31, 1969, and from January 1, 1970 through July 31, 2006 (residual radiation period)

Note: The information above is what qualified for evaluation. During our evaluation of whether dose reconstructions can adequately be completed for the above job titles and period of employment, information may cause NIOSH to change some the dates or job titles/duties. Therefore, as this petition proceeds through the SEC petition process and if an SEC class is proposed, the proposed class may not exactly match the above information.

Copy of the Petition Received

June 19, 2008 pdf icon[6 MB (96 pages)]
(January 1, 1958 through June 19, 2008)

Federal Register Notice Announcing that a United Nuclear Corp. SEC Petition has met the Minimum Qualifications for Review and Evaluation

November 28, 2008 pdf icon[42 KB (1 page)]
(January 1, 1958 through July 31, 2006)

SEC Petition Evaluation Report

August 17, 2009 pdf icon[368 KB (81 pages)]
(January 1, 1958 through July 1, 2006)

Revised February 1, 2010 pdf icon[479 KB (83 pages)]
(January 1, 1958 through July 1, 2006)

Evaluation Report Sent to the Advisory Board

September 1, 2009
(January 1, 1958 through July 1, 2006)

February 2, 2010 (Revision 1)
(January 1, 1958 through July 1, 2006)

Petition Discussed by the Advisory Board

The petition was discussed by the Advisory Board on February 10, 2010, during its regular meeting.

Note: Agendas and transcripts for Board meetings will be posted on the Advisory Board and Public Meetings page as soon as they become available.

Advisory Board Recommendation on SEC Petition

October 31, 2012 pdf icon[178 KB (1 page)]
(January 1, 1958 through July 1, 2006)

HHS Letters to Congress Regarding the SEC Petition

December 7, 2012 pdf icon[75 KB (10 pages)]
(January 1, 1958 through July 1, 2006)

HHS Designation/Determination of Additional Members to the SEC


December 7, 2012 pdf icon[33 KB (5 pages)]
(January 1, 1958 through July 1, 2006)

Note: A “designation” means that HHS is recommending a class be added to the SEC. A “determination” means that HHS is recommending a class not be added to the SEC.

Federal Register Notice: Designation/Determination Of a Class of Employees for Addition to the Special Exposure Cohort


January 2, 2013 pdf icon[50 KB (1 page)]
(January 1, 1958 through July 1, 2006)

Note: A “designation” will be published if there is a recommendation to add a class to the SEC. A “determination” will be published if there is a recommendation not to add a class to the SEC.

Effective Date for the SEC Class

Note: This only applies if the class is added to the SEC.

Federal Register Notice: Final Effect of Designation of a Class of Employees for Addition to the Special Exposure Cohort

Note: This only applies if the class is added to the SEC.

Letter to DOL Regarding the Addition of a New Class of Employees to the SEC

Note: This only applies if the class is added to the SEC.

Advisory Board Work Group on Uranium Refining Atomic Weapons Employers (AWEs)–formerly TBD 6001 Work Group

This Work Group reviews technical documents and Special Exposure Cohort (SEC) petitions for uranium refining AWEs assigned to it by the Advisory Board on Radiation and Worker Health. The Work Group makes recommendations to the Board on SEC petitions, reviews reports developed by the Board’s contractor (SC&A), and assists NIOSH and SC&A in resolving issues that arise through the review process.

Sites currently being considered by the Work Group include: General Atomics, Hooker Electrochemical, and Westinghouse Electric Corp. (New Jersey).

Meeting information (including agendas and transcripts) for this Work Group can be found on either the individual work site pages or on the Advisory Board and Public Meetings page.

Note: Baker-Perkins Co., Du Pont Deepwater Works, Electro Metallurgical Company, Nuclear Materials and Equipment Corp. (NUMEC) – Apollo, Nuclear Materials and Equipment Corp. (NUMEC) – Parks Township, United Nuclear Corp., and W.R. Grace (Erwin, TN) were previously discussed by this Work Group, but are not currently under discussion.

Work Group Members:

  • Henry A. Anderson, M.D. (Chair)
  • R. William Field, Ph.D., M.S.
  • David Kotelchuck, PhD, MPH

Meeting Information:

Pre-Decisional Document Policy

Please note that as part of the procedures and processes of the Advisory Board’s Work Groups, several kinds of pre-decisional documents may be developed. These pre-decisional documents, such as white papers, matrices, working drafts, etc., are distributed among Work Group members as research and background tools to facilitate discussion and deliberation. Although discussion during a public meeting may cover pre-decisional documents, these documents often are not further revised or finalized, and thus do not reflect the final determination or evaluation of the Advisory Board and its Work Groups. Additionally, some pre-decisional documents not otherwise posted on the website may contain sensitive information, which would require an interested party to obtain such documents by filing a Freedom of Information Act (FOIA) request with the CDC/ATSDR FOIA office at foiarequests@cdc.gov.

Technical Documents

If the energy employee’s personal radiation information is incomplete, NIOSH will use other sources to estimate the radiation dose. This may involve using technical documents called Site Profiles, Technical Basis Documents, and Technical Information Bulletins.

Technical Basis Documents

Advisory Board and NIOSH Discussions on United Nuclear Corp.

The United Nuclear Corp. discussion papers listed below are working documents prepared by NIOSH or its contractor for use in discussions with the Advisory Board on Radiation and Worker Health or its Working Groups or Subcommittees. Draft, preliminary, interim, and white paper documents are not final NIOSH or Advisory Board (or their technical support and review contractors) positions unless specifically marked as such. These documents represent preliminary positions taken on technical issues prepared by NIOSH or its contractor.

The discussion papers have been reviewed to identify and redact any information that is protected by the Privacy Act 5 USC §552a and has been cleared for distribution.

Program Evaluation Plans (PEPs) and Program Evaluation Reports (PERs)

NIOSH is committed to applying the best available science in dose reconstructions. In keeping with this commitment, completed cases with probabilities of causation less than 50% are reviewed as relevant new information becomes available. The results of these reviews are described in a Program Evaluation Report (PER). The PER details the effect, if any, of the new information on the completed dose reconstruction. If it appears that the new information may result in an increase in dose for a completed dose reconstruction with a probability of causation of less than 50%, NIOSH is committed to working with the Department of Labor to reopen and rework the dose reconstruction, as appropriate. A Program Evaluation Plan (PEP) describes plans for evaluating specific program details or issues.

  • DCAS-PER-082, Rev. 0: United Nuclear Corp. TBD Revision Program Evaluation Report pdf icon[107 KB (2 pages)]
    January 8, 2018

    About this Document: Determines the effect of revision to DCAS-TKBS-0008 (United Nuclear Corporation TBD) on previously completed claims.

    Summary: One claim resulted in a POC greater than 52%. NIOSH will provide the Department of Labor with the list of all the claims evaluated under this PER. Further, NIOSH will request the return of the 1 claim that would now result in a probability of causation greater than 50%.

Public Comments on United Nuclear Corp. Documents

How to Submit Comments

Comments on United Nuclear Corp. Documents can be submitted to the NIOSH Docket Officer electronically by email at nioshdocket@cdc.gov or printed comments can be mailed to:

NIOSH Docket Office
Robert A. Taft Laboratories, MS-C34
1090 Tusculum Avenue
Cincinnati, OH 45226
Please include the Site Profile/Docket Number (170) on all comments.

Comments Received

No public comments have been received at this time.

Document Archive for United Nuclear Corp.

Page last reviewed: September 28, 2015