EXPERIMENTAL 



The sand was tagged in 100-gram lots for the laboratory experiments. 

 The sand was placed in a l6-ounce screw-cap "bottle and the desired radio- 

 activity, in 2.25 milliliters of distilled water, was added dropwise to 

 the sand. The activity level of the added radionuclide per 100 grams of 

 sand varied from 3 to 5 million counts per minute. The bottle was capped, 

 and sand and radioactivity were thoroughly mixed by rolling the bottle on 

 a jar mill for one hour. The moist sand was then dried in an oven at 

 130-li+0°C. Then 2.25 milliliters of a 50-50 mixture of water and l+0-i+2 

 Baume sodium silicate solution was added dropwise to the sand. Contents 

 of the bottle were mixed on the jar mill for one hour, and then the 

 coated sand was dried in the oven as before. After this, the dried sand 

 was placed in a porcelain casserole and fired for one hour at 1900°F 

 (1030-I0i+0°C). 



About 5-6 grams of the tagged sand was weighed into a 15 by 125- 

 millimeter test tube. This (standard) sand sample was radioassayed each 

 time aliquots of supernates were assayed in the static leaching and the 

 abrasion tests; it served as a standard for calculating the quantity of 

 radioactivity removed in those tests. 



For the static leaching study, kO grams of the tagged sand was placed 

 in an 8-ounce screw-cap bottle along with 100 milliliters of sea water. 

 On the first day of the leaching study, 0.5-milliliter aliquots of the 

 supernate were removed and radioassayed 1, 2, and 6 hours after the sea 

 water had been added to the sand. During the following 12 to ik days, a 

 daily aliquot was removed and radioassayed. Then the experiment was 

 terminated. Before each aliquot was removed, the contents of the bottle 

 were stirred thoroughly and then allowed to settle for 5 minutes. 



For the abrasion studies, U0 grams of the tagged sand was placed in 

 a 500-milliliter bottle along with 100 milliliters of sea water. The 

 bottle was agitated in a Parr Pressure Reaction Apparatus. Aliquots 

 (0.5 milliliter) were obtained and assayed just as those for the leaching 

 experiment. As the abrasion experiment proceeded, a suspension developed 

 in the supernate. This suspension was quite stable. Therefore, the 

 radioassay included this suspended material. 



Commercial Monterey sand was used for pilot studies. After proce- 

 dures had been tested, sands from the Point Conception test site were 

 utilized. The Point Conception sands were provided by Mr. Joseph H. 

 Bittner of the Los Angeles District, Corps of Engineers. The various 

 Point Conception sands are designated according to their geographical 

 and beach locations. 



Because the tagging procedure could materially alter the size of 

 sand particles, the sand-size distributions, at various stages of the 

 tagging procedure and after the abrasion experiment, were checked with 

 a mechanically operated sieving device. In all cases the sieving lasted 

 for 15 minutes. The sieving results obtained are not to be interpreted 



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