The *U, *°U, 8U, and“Pu data were omitted primarily to keep the output unclassified. Fur-

thermore, the natural uranium contentof the soil is about one million times that received from fallout and

at least half of the plutonium in Nevada and Utah soils comes from worldwide fallout.
Surface roughnesseffects are simulated by using Beck’s values* of (mR/h)/(uCi/m?’) for a relaxation

length of 0.16 g/cm’, According to Beck, the concentration of fallout varies exponentially with soil depth,
Z, accordingto the relation C = C,e~%. He defines relaxation length as 1/a.

Fractionation effects were simulated by the removalof a fraction of the refractory nuclides from the
calculation. In general, air drops were assumed to be unfractionated, surface and cratering Events were

assumed to have 0.4 of the refractory elements present, and all other Events were assumedto have0.5 of
the refractory elements present.
Each Appendix contains 11 pages of calculated results relating to one Event in Table 1. Each set of 11
pages is marked Page 2 through Page 12 at the top and A2 through A12 (or B2 through B12,etc.) at the
bottom. Page 2 of each set gives the external gamma-ray exposure rates and associated values of total
microcuries per square meter at 30 decay intervals and at zero time. Note that the totals at zero time
ificlude only the nuclideslisted in Pages 3 through 12, not all the nuclides present at zero time. Calculated
values for each radionuclide at various decay intervals are given in the remaining pages—from 1 to 21 hin
Pages 3-7, from 1 to 300d in Page 8-11, and from 1 to 50 y in Page 12. Unless otherwise indicated, the
value for each nuclideat zero timeis the result of a radiochemical measurement. The measurements were
performed on debris samples taken byaircraft approximately 1 to 4h after detonation. The production of
nuclides designated by (*) has been estimated. When noestimate could be made, the value appears as
zero.

REFERENCES
1.

2.
3.

4.

Announced United States Nuclear Tests, July, 1945, through December, 1980, Office of Public Affairs,
Nevada Operations Office, Department of Energy, Las Vegas, NV, NVO-209, Rev. 1, January 1981.

H.G. Hicks, Calculation of the Concentration of Any Radionuclide Deposited on the Ground by Fallout from
a Nuclear Detonation, Lawrence Livermore National Laboratory, Livermore, CA, Preprint UCRL-86177
(1981). Accepted for publication in Health Physics.
E. Hardy, Plutonium in Soil Northeast of the NevadaTestSite, Environmental Measurements Laboratory,

Department of Energy, New York, NY, HASL-306, pg. 1-51, July 1, 1976.
H.L. Beck, Exposure Rate Conversion Factors for Radionuclides Deposited on the Ground, Environmental
Measurements Laboratory, Department of Energy, New York, NY, EML-387, July, 1980.

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