APPENDIX F RATE OF DEPLETION OF STRONTIUM IN SOIL by A. E. Brandt The and the not following calculations utilize our data on sr89-90 in soil milk bone. Although the calculations are based on the two isotapes, depletion rates are unaffected as the decay of the isotope@ has been considered. Case I = Cows Live on Fasture TOTAL RADIOSTRONTIUM IN SKELETON OF 1200 LB. DAIRY COW me Radiostrontinum in Bone Grams of Ca. in d/m/egr. Ca. in Bones of From Ave. (1200 lb.) — Dairy Cow 7 From O00 To 12000 To ~~ 11 56000 88000 84000 132000 TOTAL RADIOSTHONTIUM PER YEAR IN MILK OF AVERAGE DAIRY co (6000 lbs. of Milk) in d/m Grams of Ca. Radiostrontium in Bone Per Year in in d/m/er. Ca. Milk of Ave, From Dairy Cow 3500 To 309 ooh 13650 22h09 If we assume the average dairy cow of 1200 pounds will sveragq 6000 pounds of milk per year for 10 years, after two years growingl|up we can arrive at a first estimate of her annual removal of stron}ium from the soil as follows: she will remve the radiostrontiumfin her skeleten which, according to figures now available, should lig be- tween 56000 and 132000 d/m. She will remove the radiostrontigm in her milk which according to data now available, should lie befween = 9] =