United Nuclear Corp.

Facility Description

The United Nuclear Corporation in Hematite, Missouri, processed unirradiated uranium scrap for the AEC, recovering enriched uranium from it for use in the nuclear weapons complex. Mallinckrodt Chemical Works owned the Hematite plant until 1961.

During the period of residual contamination, as designated by the National Institute for Occupational Safety and Health and as noted in the dates above, employees of subsequent owners and operators of this facility are also covered under the Energy Employees Occupational Illness Compensation Program Act.

1. Introduction and Purpose
United Nuclear Corporation (UNC), located in Hematite, Missouri, manufactured uranium metal and uranium metal compounds from natural and enriched uranium for use as nuclear fuel. The facility became operational in 1956, initially producing uranium products for use in the naval fuel program. Specifically, the site was used to convert government-owned and leased uranium hexafluoride (UF6) gas of various uranium-235 (U-235) enrichments to uranium oxide, uranium carbide, uranium dioxide pellets, and uranium metal. These products were manufactured for use by the federal government and government contractors and by commercial and research reactors approved by the Atomic Energy Commission (AEC). Research and development was also conducted at the site, as were uranium scrap
recovery processes.

2. Background
From its inception in 1956 through 1974, the Hematite facility was used primarily in support of government contracts that required production of high-enriched uranium (HEU) products. From 1974 through the plant closure in 2001, the focus was on commercial fuel production. The Hematite plant used enriched uranium derived in part from recycled fuel, resulting in the potential for the presence of trace amounts of transuranic radionuclides, neptunium-237 (Np-237), plutonium-239/plutonium-240 (Pu-239/240), and americium-241 (Am-241). For an approximately nine-month period in 1964, UNC also blended thorium dioxide powder with uranium dioxide powder to produce fuel pellets for use in fuel assemblies for the Elk River Reactor (Pellet Plant Data, 1964; Swallow, 1963; Swallow, 1964a).

The primary source of the internal radiation exposure was deposition of alpha-emitting materials via inhalation and ingestion of airborne uranium and thorium (and progeny). Operations at the UNC-Hematite facility potentially would have resulted in external exposures primarily to uranium and uranium decay products.
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