Ingestion of Three Radionuclides Added to Huntington Pilot Plant Employee Dose

Updated 5 years ago by Tony E. Rutherford, News Editor
Ingestion of Three Radionuclides Added to Huntington Pilot Plant Employee Dose

Dose reconstructions for workers at the former uranium processing Huntington Pilot Plant (Reduction Pilot Plant) have been revised to include  Americium-241, Thorium 230 and Technetium-99, according to the National Institute for Safety and Health (NIOSH) Division of Compensation  Analysis and Support. The adjustment was made November 30, 2015.

NIOSH has re-calculated all claims that had a less than 50%  probability of causation.  However, the alteration resulted in only two out of 57 that fell between 45% and 50%.

"Since none would now result in a POC greater than 50%, NIOSH will not request the return of any of the claims to the Department of Labor," the document said.

The HPP/RPP processed uranium and nickel carbonyl nuclear fuel for use at three former gaseous diffusion plants in Portsmouth, Ohio; Paducah, Ky.; and Oak Ridge, Tenn.  The Atomic Energy Commission (AEC) leased the location located on the International Nickel / Huntington Alloys / Special Metals property. The classified facility operated from about 1951-1962 when it was placed on cold stand by until 1978. At that time, the building was disassembled and radioactively contaminated portions taken by truck and rail and buried at a landfill at the Portsmouth Gaseous Diffusion Plant, Piketon, Ohio.

Certain former HPP/RPP employees qualify for nuclear workers compensation, if they contracted specifically determined cancers.

Americium 241 is a prevalent isotope found in nuclear waste. Americium-241 decays by alpha emission, with a by-product of gamma rays. Its presence in plutonium is determined by the original concentration of plutonium-241 and the sample age. Because of the low penetration of alpha radiation, Americium-241 only poses a health risk when ingested or inhaled. Older samples of plutonium containing plutonium-241 contain a buildup of 241Am. A chemical removal of americium from reworked plutonium (e.g. during reworking of plutonium pits) may be required.

Thorium 230 (Th 230) Thorium was once commonly used as the light source in gas mantles and as an alloying material, but these applications have declined due to concerns about its radioactivity. Thorium is also used as an alloying element in TIG welding electrodes. It remains popular as a material in high-end optics and scientific instrumentation; thorium and uranium are the only radioactive elements with major commercial applications that do not rely on their radioactivity. Thorium is predicted to be able to replace uranium as nuclear fuel in nuclear reactors, but only a few thorium reactors have yet been completed. For a discussion of possible Thorium reactor use, watch the You Tube video discussion.

Technetium-99 (Tc99) decays with a half-life of 211,000 years to stable ruthenium-99, emitting beta particles[1], but no gamma rays. It is the most significant long-lived fission product of uranium fission, producing the largest fraction of the total long-lived radiation emissions of nuclear waste. Technetium-99 has a fission product yield of 6.0507% for thermal neutron fission of uranium-235.