ADDENDUM C-2 



Xenon- 133 Tagging Procedure 



Preparation of Sand 



Sand from the test area which had been shipped to OKNL for treatment 

 and labeling was screened with a 10 mesh screen to remove debris, washed 

 with tap water, and covered with hydrochloric acid. The acid concentra- 

 tion was not critical but should be >6 I. The mixture was held in a well- 

 ventilated area for ~2^ hr and occasionally stirred/ until all signs of a 

 reaction with carbonates had ceased. After the sand was thoroughly washed 

 to remove the acid and dried, it was ready for high-temperature tagging 

 with 133 Xe. 



Tagging Procedure 



A 58-kg batch of prepared sand was loaded into a specially designed 

 furnace (see Addendum C-3). The furnace was placed in a shielded cell 

 equipped with manipulators, connected to a gas purification system (see 

 Fig. C-8), and heated to 600°C. The gases evolved from the sand during 

 heating were removed with a vacuum pump. At 600°C, pumping was discon- 

 tinued (pressure is ~0.03 cm of Hg), and 133 Xe was admitted into the 

 furnace. The furnace was further heated to 850°C (requires ~3 hr) and 

 was then cooled, first to 150°C by circulating N 2 gas that had been cooled 

 wj.th liquid N 2 through the cooling coils, and then to ~80°C by water. 

 The excess 133 Xe was recovered by pumping the gas mixture through traps 

 cooled with liquid N 2 . These traps recovered 133 Xe and allowed the bulk 

 of the gas contaminants (N 2 and 2 ) to. pass through. The gas pressure 

 in the furnace after 133 Xe addition was <L cm of Hg. After the furnace 

 was heated and cooled, the pressure was ~150 cm of Hg. The sand was re- 

 moved and then packaged in gallon paint cans . With a 133 Xe concentration 

 of 8 mCi/cm 3 in the gas phase, the sand will adsorb ~20 u-Ci of 133 Xe per 

 gram of sand . 



C-24 



