Fallout Fractionation in Silicate Soils
Abstract
The existing models for treating fractionation in nuclear weapon debris are discussed and compared. A method which extends the existing theory for the case of surface bursts over silicate soils is developed and validated with weapons test data. Fission product uptake is modeled as follows: The weapon debris and some soil is fully vaporized. Some soil is merely melted. As the fireball cools, the refractory fission products are absorbed by this liquid material. After the fireball has cooled below the soil solidification temperature, the remaining fission products can be adsorbed onto any available surfaces. Soil which enters the fireball after the soil solidification time will also adsorb fission products. Test data and other evidence indicate that the distributions of melted and unmelted soil particles have different modes. This model uses diffusion theory to transport the fission products into the particles. In addition, it allows for injection of unmelted material near the time of soil solidification. The results of the research indicate that in standard DELFIC calculations too much activity is carried in the larger particles. In addition, the distribution of volatile fission product nuclides relative to a refractory reference nuclide is in general better modeled by the new method. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1983
- Accession Number
- ADA159226
Entities
People
- Charles R. Martin
Organizations
- Air Force Institute of Technology