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g UNITED STATES ATOMIC ENERGY COMMISSION
.,, q'f IDAHO OPERATIONS OFFICE P. O. BOX 2tod IDAHO FALLS. IDAHO 83401 May 23, 1973 Mr. R. Jerrel Everett Directorate of Regulatory Operations - Region I U. S. Atomic Energy Commission 970 Broad Street
. Newark, New Jersey 07102
Dear Jerry:
Enclosed is a report of the special study carried out on the 0yster Creek February rad waste composite. Similar problems were identifl W in the Cubitainer and glass bottles used on May.2, 1973, for collection of the special samples from Oyster Creek's Waste Tank B.
Additional studies on various samples from other nuclear power plants indicate that fractionation of radionuclides between filtrate, filterable resterial, and container walls is a serious common problem.
As you may already know, the information will be presented by Claude Sill
-at the Albany meeting, May 22 thru 24, 1973. A summary report on all the studies carried out to date will be made available soon. We are giving this problem top priority and will keep you informed of our progress.
Very truly yours, n
%*> t Donald R. Percival Acting Chief, Chemistry Section Analytical Chemistry Branch Health Services Laboratory
Enclosure:
Report b
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9604150055 960213 PDR= FOIA DEKOK95-258 PDR-
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DISTRIBUTIONS OF MANGANESE-54 AND COBALT-60 l
IN THE HEALTil SERVICES LABORATORY SPLIT' 0F AN OYSTER CREEK RAD WASTE COMP 031TE SAMPLE
!!calth Services Laboratory U. S. Atomic Energy Commission 1
Idaho Falls, Idaho:83401 April 1973
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On April 13, 1973, Dr. David McCurdy, State of New Jersey Department'of Environmental Protection, advised the 11ealth Services Laboratory (llSL) that his manganese-54 and cobalt-60 results on the February 1973 rad.
waste composite from Oyster Creek were considerably higher than the liSL results. The two laboratories' results for strontium-90.ccalum-134, and cesium-137, however, agreed quite well.
Dr. McCurdy suggested diat the llSL check for losses of manganese-54 and cobalt-60 on the walls of the polyethylene Cubitainer in which the sample was sent.
Dr. McCurdy stated that his splits were collected in glass bottles and analyzed within two days after collection.
-The sample had been made 10% volume / volume with concentrated ilNO3 on or before the collection date of March 2, 1973. On March 9, the HSL per-formed a gamma spectral analysis on an unfiltered 400-m1 aliquot.
On April 13, the'210 ml of sample remaining in the Cubitainer was filtered through a.O.45-micron membrane filter, and the activity remaining in the empty container was subsequently removed quantitatively with successive acid washes. Each fraction was analyzed by gamma spectrometry. The radionuclides identified and their distributions on April 13, 1973, are presented in Table 1.
The itSL results for manganese-54 and cobrit-60 on March 9 and April 13, 1973, are presented in Table II.
The-March 9 results were obtained on a 400-m1 aliquot of unfiltered sample. Unfortunately, the aliquot had been discarded and was not available for reexamination on April 13. The April 13 results were obtained on the filtrate from the 210 ml of sample remaining in the Cubitainer on that date. The results on the filtered and unfiltered samples agree suprisingly well. Apparently, the insoluble material in the March 9 aliquot was not representative of nor proportional to the insoluble material present in the Cubitainer on April 13.
Estimates of the manganese-54 and cobalt-60 concentrations attributable to filtrate, filtered material, and walls of the Cubitainer are shown in Table III. The estimates were based'on the following assumptions:
(1) The filtrate of April 13, 1973 was identical to the unfiltered 400-m1 aliquot analyzed on March 9, 1973.
(2) The original volume of the sample, although not precisely known, was assumed to have been 900.ml.
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.A (3).No significant losses of manganese-54 and cobalt-60 activities associated with filterable material occurred in the aliquots taken for various analyses between March 9 and April 13, 1973.
The concentrations of manganese-54 and cobalt-60 attributable to filterabic material, therefere, are simply 1/900 of the' total activities determined on April 13, 1973.
(4) The manganese-54 and cobalt-60 activities adhering to the walls of the Cubitainer had reached a maximum by March 9 and remainet!
constant thereafter. Therefore, the equivalent concentrationn are 1/900 of the total activitics' determined on April 13, 1973.
Correction of the totals in Table III for dilution of the sample with llNO3 and for decay of manganese-54 gives (11.611.3)x10-6 pCi/mi for manganese-54 and (25.7tl.3)x10-6 pCi/ml for cobalt-60. The New Jersey *results were t
(11.210,5)x10-6 pCi/ml and (26.711.3)x10-6 pCi/ml. The ratios, HSL/New Jersey, are 1.0410.13 and 0.96 0.07 for manganese-54 and cobalt-60, respec-tively. The HSL cobalt-60/ manganese-54 ratio is 2.2210.27 and New Jersey's ratio is 2.3810.16.
The agreement between the original New Jersey results and the HSL results of April 13, 1973, is probably fortuitous since the latter were obtained using rather tenuous assumptions with data on the remainJng 23% of a sanple that was 42 days old. However, the important point is the identifica tion of a serious problem affecting the entire laboratory intercomparison pro-
. gram. Preliminary studies indicate that a similar and equally serious problem exists with samples collected in Cubitainers at other reactor faci-lities using the procedure recommended by the HSL. That procedure involves the addition of 20 m1 nf concentrated hydrochloric acid and 100 mg of NallS0 3
per liter of sample.
Dr. McCurdy suggested the use of glass rather tnan plastic containers ~as a possible solution to the problem. Accordingly, the HSL has requested the special collection of two samples of the April rad waste composite from Oyster Creek, one in glass and one in a Cubitainer.
Additional studies are being made by the HSL to solve this problem. Results and recommendations will be made available as soon as possible.
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TABLE I.
' DISTRIBUTION OF ACTIVITIES ON APRIL 13 1973.
Net Cpm-Fraction 5%Kn 60co seco 51Cr 134Cs 137Cs
-957b 5 3 pe..
124Sb Filtratel 10.111.2 26.8tl.5 4.912.1 9813
.121 3 10-minL 70-m1 agua regia wash 2 29.811.0 38.511.1 3.1 0.6 3.710.7 3.7t0.6 2.020.5 0.910.2 0.2+0.
4 10-min 70-m1Lconcentrated hcl 13.8t0.6 15.9!0.6 1.2iO.3 0.910.3 0.410.1 L+H02 2 wash'
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70-ml.dllute hcl *IF
'Over weekend-26.010.8 39.6 0.9 2.510.5 2.010.4
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Overnight 2.2 0.3 3.9!0.3 SUBTOTAL MASIIES 71.811.4 97.911.6 7.It0.8
~ Filter 3 14.011.0 22.8 1.1 2.110.6 Weshes + Filter 85.811.7 120.7tl.9 4.310.7 3.710.7 9.2tl.0.
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TOTAL CP!!
95.922.1 147.512.4 4.310.7 8.6t4.9 9813 130.213.2 4.010.6 -
1.310.2' O.210. _
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%'in Filtrate 10.5!1.3 18.2 1.1
% on Filter 14.621.1 15.510.8 Z on Bottle 74.9!2.2 66.411.5 1
. I Activity in total 210 ml of filtrate based on analysis of a 70-n1 aliquot.
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i 2A11. acid washe< were evapora ted to 70 m1 for ganma spectroc:Otry.
3The membrane filter was wet-ashed and Jiluted to 70 ml for-'nanna.socctrometry.
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. TABLE II. ' MANGANESE-54 AND COBALT-60 CONCENTRATI0:IS, uCi/ml March 9 1973
' April 13 1973 56Mn.
'(3.8 0.2)'x 10-6 (3.2 2 0.3) x l'0-6 60 (1.24 1 0.03) x 10-6 (1.13 2 0.07) x 10-6 Co e
TABLE III. ESTIMATES OF MANGANESE-54 AND COBALT-60 CONCENTRATIONS IN THE ORIGINAL SAMPLE ASSUMING HOMOGENEITY Activity Attributable to Each Fraction 3 Mn
'UCo Fraction pCi/mi x 100 pC1/mi x IOb Filtrate 3.2 1 0.3 34 1 5 11.3 2 0.7 49 2 4 Filter 1.0 2 0.2 10 2 2 2.2 0.2 10 2 1 Cubitainer 5.3 1.0 56 1 12 9.6 t 1.0 4125 TOTAL 9.5 1 1.1 23.1't 1.2 m.-. --
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