for sample 2476. The results of the other quality control samp: jo in this and earlier reports attest to the overall reliability or the plutonium analyses. Therefore, it is likely that @ sample s of the plutonium fraction of sample 2476 took place during analy: a although no positive evidence of such a switch was found. A thixz duplicate of this sample will be submitted for Pu analyses to ver this conclusion. REFERENCES {1} Krey, Project Airstream USAEC Report HASL-183, P., Ww. October (1967) (2) Ibid, USAEC Report HASL-184, January (1968) (3) Ibid, USAEC April (4) <Ibid, USAEC Report (5) Ibid, USAEC (6) Ibid, USAEC Report HASL-207, April (7) Thid, USAEC Report HASL=210, Culy (1969) (8) Tbid, USAEC Report HASL-217, (9) Krajewski, B. Calculations of Stratospheric Air Sample Volumes Report HASL-193, (1968) HASL-197, TJaly (1968) Report HASL-204, January (1969) (1969) January (1970) USAEC Report HASL-211, July (1969) II ~ 16 wy,