PNNL

Abstract

Technetium-99m (99mTc) is the most widely used radioisotope for medical procedures. It is used to diagnose and stage serious medical conditions such as heart disease, cancer, infection, and inflammation. 99mTc is used in more than 40,000 imaging procedures daily in the United States and at least an equal number of procedures throughout the rest of the world. Molybdenum-99 (99Mo) is the parent isotope of 99mTc. For more than 25 years, the U.S. supply of 99Mo has been solely reliant on aging nuclear reactors located outside the United States, resulting in supply interruptions that disrupt the provision of healthcare for patients. Eden Radioisotopes, LLC, is attempting to design and build a less than 2-MW nuclear reactor for the sole purpose of providing 99Mo. This reactor would be a small, dedicated reactor for medical isotope production. While the small size and single mission result in relatively low atmospheric emissions, it is still important to optimize design of the atmospheric effluent system to minimize dose to member of the public. Here, the EPA-approved atmospheric model CAP-88 PC is used to compare some various effluent design considerations, and the resulting dose from atmospheric emissions. In this report, the difference in estimated dose to a maximally exposed individual, as well as the location of the potential receptor are estimated for various stack heights, velocities and exhaust rates. Additionally, another EPA-approved model, COMPLY, is tested to evaluate the similarity in the estimated doses between the two models.