Session: OAC-04-02 Transportation of Radioactive and other Hazardous Materials II

Paper Number: 61863

Start Time: Thursday, July 15, 2021, 09:00 AM

61863 - A Simple Method to Estimate Airborne Release Fractions Associated With the Pressurized Release of Radioactive Materials 

Radioactive materials, such as plutonium bearing oxides, are stored in 3013 containers at the US Department of Energy Savannah River Site (SRS) near Aiken, South Carolina.  The 3013 containers are packaged in 9975 shipping packages which are palletized for long term storage.  The triple nested 3013 containers are each made of stainless steel.  The outermost 3013 container is designed to the ASME BPV Code with a 699 psig design pressure and utilizes a welded closure.

Pressurized release of radioactive materials, such as plutonium bearing oxides, could occur during a fire accident event where a robust container holding the radioactive materials ruptures catastrophically due to excessive pressurization.  The common source of pressurization is the vaporization of water adsorbed onto the actinide oxides.  A simple theoretical approach based upon NUREG/CR-6410 is presented which allows calculation of airborne release fractions for pressures up to and above 500 psig.  A parametric study is used to determine the level of bias (conservative or non-conservative) when the approach is applied to DOE-STD-3013 welded stainless steel containers which are used to store plutonium bearing oxides at the US Department of Energy Savannah River Site.  The event considered is a 3013 container subjected to a hypothesized facility fire where the container fails catastrophically and ruptures resulting in a vented high pressure release of the plutonium bearing oxide materials. The parametric study shows that the simple method for calculating airborne release fractions is biased high by about 45% compared with the detailed approach of NUREG/CR-6410 when used to quantify the amount of material released from a 3013 container rupture.

Presenting Author: Steve Hensel SRNS

Authors:

Steve Hensel SRNS
Ray Sprankle SRNS