ML20133Q405
| ML20133Q405 | |
| Person / Time | |
|---|---|
| Site: | Wood River Junction |
| Issue date: | 10/16/1985 |
| From: | Berger J OAK RIDGE ASSOCIATED UNIVERSITIES |
| To: | Crow W NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| Shared Package | |
| ML20133Q395 | List: |
| References | |
| 25946, NUDOCS 8511010533 | |
| Download: ML20133Q405 (2) | |
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@ Dorcd Oak Ridge Manpower Education, Associated Post Office Box 117 Research, and Training Universities Oak Ridge, Tennessee 37831-0117 Division j
October 16, 1985 Mr. William Crow Division of Fuel Cycle & Materials Safety E
NMSS-SS3%, Nuclear Regulatory Commission Washington, DC 20555 i
j
SUBJECT:
ISOTOPIC URANIUM IN UNC SOILS
Dear Mr. Crow:
i UNC has questioned whether the average U-234/U-235 ratio of 3_5, determined 5
for soils from beneath the columns area, is appropriate for other soils at the j
Wood River Junction site. According to UNC'c vendor laboratory, there are much lower relative levels of U-234 than our analysis has indicated.
To help resolve this matter, ten archived samples of soil, collected during our survey of the restricted area of the site, were selected; a small aliquot (about 20 grams) was withdrawn from each sample; and this aliquot was analyzed by l
alpha spectroscopy for isotopic uranium.
Results are presented in the attached table.
Most of these samples contain low concentrations of U-23 5, resulting in large relative uncertainties.
However, the presence of U-234 was readily detectable in all samples. The U-234/U-235 ratios range from 21.6 to 73.5, but six of these ratios have large associated uncertainties.
The ratios of the remaining four samples range from 21.6 to 47.0 with an average of 32.7.
I believe these additional results further confirm that U-234 is a major contaminant in the residues at the Wood River Junction site and that the U-234/U-235 ratio is on the order of 30 or greater, as would be expected in enriched uranium.
I-If you have questions concerning there results, please contact me at i
FTS 626-3305.
Sincerely, t
su
_ James D. Berger Program Manager Radiological Site Assessment Program JDB:mec Enclosure Jerry Roth, Nuclear Regulatory Commission, Region I cc:
8511010533 851029 PDR ADOCM 07000820 C
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ISOTOPIC URANIUM CONTENT OF SOIL l
SAMPLES FROM UNC RESTRICTED AREA Sample Uranium Concentrations (pCi/g) l ID U-234 U-235 U-238 U-234/U-235 3457 10.7 + 2.la 0.41 + 0.40 1.34 + 0.73 26.0b 1
[
3468 17.7
_ 2.9 0.24 _+ 0.33 0.96 _+ 0.67 73.5b i
+
3478 152
+2 5.55 + 0.43 2.59 + 0.29 27.4 a
3489 8.89 + 0.94 0.41 + 0.20 0.41 + 0.20 21.6 i
i 3496 15.9 + 1.9 0.30 + 0.27 0.79 + 0.43 52.4b i
j 3539 29.3 + 2.7 0.40 + 0.32 0.60 + 0.39 73.0b 3584 31.8 + 2.3 0.68 + 0.33 1.02 + 0.41 47.0 3599 9.19 + 1.54 0.27 + 0.27 0.14 + 0.19 34.0b 3602 461
+5 13.3 + 0.8 1.46 + 0.28 34.6 3608 6.09 + 1.02 0.18 + 0.18 0.40 + 0.26 34.0b Average 32.7 1
aErrors are 2a based only on counting statistics.
b l
Not used in average because of large relative error.
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