SUMMARY REPORT FOR ZINC 65 CONTAMINATION CONTROL

Radioactive zinc, {sup 65}Zn, was detected after extraction of 215 TPBARs in from TVA reactor fuel cycle 6. A team consisting of Tritium Engineering, Tritium Operations, Tritium Radiation Control, and Savannah River National Laboratory personnel evaluated the risk and response and developed short, medium and long term goals for contamination control. One of the goals was incorporated into site Performance Based Incentive CO 3.4, to optimize the filter geometry and operating conditions for the Tritium Extraction Facility. This goal included a scoping study to determine if the contamination could be contained within the high radiation environment of the furnace module as well. In order to optimize the filters studies were conducted to independently evaluate the effect of pore size on pumping efficiency and zinc trapping efficiency (1). A study was also conducted to evaluate the effect of temperature on the trapping efficiency and adhesion (2). In addition, the potential for chemically trapping zinc in the lithium trap was evaluated using a thermodynamic study (3) followed by preliminary experimental testing (4). Based on the work that was completed it is determined that a 20 {mu}m filter heated to between 120 and 200 C will act as an effective physical trap for zinc vapors. It may be possible to chemically react zinc with copper or cobalt to form zinc intermetallic compounds or alloys but additional work under more prototypic conditions are required