SWRHL-46r
        PARTICULATE EFFLUENT STUDY
               PHOEBUS  IB,  EP-IV
                       by the
    Southwestern Radiological Health Laboratory

U. S. Department of Health, Education,  and Welfare
               Public Health Service
           Environmental Health Service
                     April  1970
This surveillance performed under a Memorandum of
           Understanding  (No. SF 54  373)
                       for the
       U. S. ATOMIC ENERGY  COMMISSION

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                         LEGAL NOT TCP:

This report was prepared as an account of Government sponsored
work.  Neither the United States,  nor the Atomic Energy Commission,
nor any person acting on behalf of the Commission:

A.  Makes any warranty or representation,  expressed or implied,
with respect to the accuracy, completeness,  or usefulness of the in-
formation contained in this  report, or that the use of any information,
apparatus, method, or process disclosed in this report may not in-
fringe privately owned rights; or

B.  Assumes any liabilities with respect to the use of, or for damages
resulting from the  use of any information, apparatus,  method, or pro-
cess disclosed in this report.

As used in the above,  "person acting on behalf of the Commission" in-
cludes any employee or contractor of the Commission,  or employee
of such contractor,  to the extent that such employee or contractor of
the Commission, or employee of such contractor prepares, dissemi-
nates,  or provides access to, any information pursuant to his employ-
ment or contract with the Commission,  or his employment with such
contractor.
      019

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                                                  SWRHL-46r
         PARTICULATE EFFLUENT STUDY
               PHOEBUS IB,  EP-IV
                       by the
    Southwestern Radiological Health Laboratory

U. S. Department of Health, Education, and Welfare
               Public Health Service
           Environmental Health Service
       Environmental Control Administration
           Bureau of Radiological Health
                    April 1970
This surveillance performed under a Memorandum of
           Understanding (No. SF 54 373)
                      for the
       U. S. ATOMIC ENERGY COMMISSION

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                            ABSTRACT





The Southwestern Radiological Health Laboratory (SWRHL) of the



U.  S. Public Health Service performed,  under a memorandum of



understanding with the AEC,  a study concerned with delineating the



physical and chemical characteristics and  possible hazards asso-



ciated with release of particulate matter (greater than several



microns in diameter) from the Phoebus IB, EP-IV reactor run con-



ducted February 23,  1967.   The reactor test was part of the Project



Rover Program and was conducted at Jackass Flats, Nevada.




The particle deposition occurred in a general northerly  direction



from  the test cell. Particles were found out to 82 miles with the



results  indicating a decrease in  deposition (particles/unit area) with



distance to about the  2. 5 power.  The particle  size distribution, of



all  the particles collected,  is reasonably described by a log normal



distribution with a geometric mean diameter of about  12|j. and a



geometric standard deviation of  2.1.  A  breakdown of the size



distribution to those particles 10|j. and above gave a geometric mean



of 26|j. and geometric standard deviation  of 2.




The density of 8 particles (12 - 28fi) was found to be about 11 g/cc.



This density indicates an equivalent aerodynamic geometric mean



diameter  of about 40|j. .  Thus, the majority of the particles found



and studied were larger than an  equivalent diameter of lOjjt -  the



usual cut-off for lower respiratory tract penetration.  A regression



analysis indicated a decrease in particle size and activity with



distance.





Isotopic results showed a large degree of fractionation of the fission

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products found in the particles.





Electron microprobe analysis indicated uranium,  carbon, and



oxygen to be present in most of the particles analyzed.





Particles were transported into the off-site area.  The resulting



ground concentrations were  about  1 particle/100 m2 or less and there



was no known interaction of  particles with people from the general



population.  Thus it is concluded there was no hazard to  the public



from the "particulate effluent. "
                                11

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                      TABLE OF CONTENTS


ABSTRACT                                                      i

TABLE OF CONTENTS                                        iii

LIST OF TABLES                                               iv

LIST OF FIGURES                                               v

I.    INTRODUCTION                                             1

II.   RESULTS AND DISCUSSION                                  4

     A.  Particle Concentration with Distance                     7

     B.  Particle Size Distribution                              10

     C.  Radioactive Constituents of Particles                   14

     D.  Correlation of Particle Size, Gross Activity and
        Distance                                               17

     E.  Elemental and Chemical Composition                   22

     F.  Particle Density                                       27

     G.  Biological Clearance Rates                            28

III.  SUMMARY AND  CONCLUSIONS                            30

REFERENCES                                                 34

APPENDICES
DISTRIBUTION
                               111

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                         LIST OF TABLES

Table 1.     Particle size distribution                           14
Table 2.     Results of isotopic analysis of particles (pCi)        16
Table 3.     Correlations of  size, activity and distance           18
Table 4.     Results of electron microprobe analysis             24
Table 5.     Location,  size,  and total isotopic activity of
             particles                                            26
Table 6.     Density of particles                                 28
                                 IV

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                        LIST OF FIGURES
Figure 1.     Particle sampling areas.                          5

Figure 2.     Reactor Test ground deposition pattern for
              Phoebus IB, EP-IV, 24 February 1967.            6

Figure 3.     Hodograph for Jackass Flats, Phoebus IB,
              EP-IV.  ,                                         8

Figure 4.     Number of particles per 100m2  versus distance
              (miles).                                          9
Figure 5.     Particle size distribution, Phoebus  IB,  EP-IV.   11

Figure 6.     Log probability  plot of 109 particles (size in
              microns).                                        12
Figure 7      Particle size versus distance from test  cell.       20

Figure 8.     Survey meter readings of particles versus
              distance from test cell (beta + gamma with G.M.
              instrument).                                     21

Figure 9.     Estimated downwind transport distance for
              various size particles.                           23

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                        I.  INTRODUCTION


Project Rover reactor tests are conducted at the Nuclear Rocket

Development Station (NRDS), Jackass Flats,  Nevada.* The station

is about 90 miles NE of Las Vegas, Nevada.

The Project Rover reactors are based on a single pass gas-cooled

design.  The reactor cores are composed of annular fuel rods made

up of UC  beads in a graphite matrix.  The coolant, hydrogen,  is

passed through the core  and expelled to the environment via the

reactor nozzle.  The hydrogen is burned after exiting from the

reactor and this thermal energy, plus the  effluent kinetic  and

thermal energy, produces a cloud or effluent rise of better than

1500 meters.

It has been noted over a  period of several  years that the effluent

from Project Rover reactor runs contains large radioactive par-

ticulate matter in addition to gaseous and normal atmospheric size

particulate matter.  The large particulate matter is composed  of

actual  segments of the reactor core released by what  is termed the

"corrosion process," whereas the  radioactive gaseous effluent

results from diffusion of the fission products in the core.   The

particles can contain fission product inventories up to the order of

microcuries in quantity.  Several of the particles were detected

30 miles downwind of the test cell after the NRX-A5,  EP-IV test

on June 23,  1966 (1400 - 1430 PDT).  This discovery, coupled  with
*The Project Rover Program is charged with development of a
 nuclear reactor for rocket propulsion for deep space exploration.
 The program is administered by SNPO, the Space Nuclear
 Propulsion Office.

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increasing reactor power, caused concern about the possible
                                                                    6
hazards associated with the deposition of particles in populated areas.

The physical harm from interaction of these particles with individuals

is not fully understood.  Areas of possible concern are  skin, eye,

and lung doses.  This report is concerned primarily with determining

the physical parameters of the effluent versus other studies concerned

with their biological interaction.

This report presents the results of particle  studies for  the Phoebus IB

test series, Experimental Plan IV conducted by the Southwestern
            i
Radiological Health Laboratory. * It supersedes our previous

reports on the subject.  The event was conducted at_1400 PDT  on

February 23,  1967, at Test Cell C,  NRDS.  The reactor was in the

inverted position, with the effluent expelled  vertically upward. The

power integral was about 3 x 106 Mw-sec with 30 minutes

(1400-1430 PST) at full power, 1500 Mw.  The work reported here

was performed under a memorandum of understanding between the

Public Health Service and the Atomic  Energy Commission who are

responsible for off-site safety.  Effluent from the reactor test was

distributed in a general northerly direction.  Particles  were found

up to 82 miles from the reactor.


Project Objectives

The general objectives of the SWRHL studies were to determine the

extent of downwind deposition of particles and their chemical and

physical characteristics.  Specifically the objectives were to de-

termine an indication of the following:

        A.  Downwind concentration of the particles on the ground as
 *The Phoebus IB test series was conducted by the Los Alamos
 Scientific Laboratory as part of the reactor development program
 for Project Rover.

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            a function of distance from the test cell.  The prime
            emphasis was on downwind instead of crosswind
            concentrations.

       B.   Particle size  distribution for all of the particles and for
            various distances downwind.

       C.   Constituent radioactive composition of the particles:
            1.  Gross alpha,  beta,  and gamma.
            2.  Specific isotopic composition - including the
               isotopic fractionation.

       D.   Correlation of the parameters:  particle size, activity.
            and distance of collection.

       E.   Elemental and chemical composition.

       F.   Particle density.

       G.   Possible hazard to the general population in the off-site
            area.
After collection of the particles,  a  few were used in a study of
biological clearance rates in rats.  The  primary objective of the
study was to develop methodology for future studies.

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                  II.  RESULTS AND DISCUSSION

During a six-day period after the reactor test, 53 areas, generally
300 ft2 or more in area, were surveyed for particles using an open
window E-500B survey instrument held about 6 inches above the
ground (see Appendix A for methods).  The areas surveyed were in
a northerly direction from Test Cell C at distances between 9 and
115 miles.  The sampling locations were chosen on the basis of
particle survey results, vegetation profiles,  tracking by aircraft,
and to some extent by terrain features.
Particles were located in 21 of the monitored areas and 228 indica-
tions of particles were obtained. * This information is  presented in
Figure 1 and Appendix B. The general effluent hotline, based on
three arcs where vegetation samples were collected (two on-site
and one on Highways 6  and 25) and the  area of highest air concen-
tration (according to air samples taken along Highway 25), is also
indicated in Figure  1.  Specific  results for air and vegetation
samples are given in Reference  1.
Figure 2 indicates the fallout deposition pattern determined by
Edgerton,  Germeshausen and Grier, Inc. on February 24.  The
pattern was determined using a calibrated crystal in an airplane
flying at about  500 feet above the surface.
 ^Effluent from reactor cool-down was carried by the night-time
 drainage winds over the Lathrop Wells area (approximate azimuth
 210°).  This area, along Highway 95, was monitored on February 27
 and there was no indication of particulate activity.

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                          Warm Springs
                Vegetation Arc -               O
                  Tonopah to Coyote Summit
                               35O
                                                        Approximate Hotline
                                                        (As determined by
                                                        vegetation samples)
                         -N-
                             1O
                       MILES
              Phoebus 1B EP IV
                 Reactor  Test
              Discussed on  page A
                    Locations surveyed
              for particles. Number
              indicates particles found
              normalized to 1OO m2.
                      Vegetation Arcs
              Beatty
                                                               Highest A
                                                               Sample Result
Queen City
       Summit
                                                          Yucca A.S.
                               Test Cell "C"
Figure 1.  Particle  sampling areas.

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    NOTE: Dose rates shown
      are net increase above
      background.


    Isodose Contours
     (measured)

    Isodose Contours
     (interpolated)

    Aircraft Flight
     Path
                                               Site
                                 JACKASS FLATS
.04  MR/HR
                                                                    O4-.O8 MR/HR
                                                                     .O8-.12 MR/HR
                                                                     .12-.2O MR/HR
                                                                     2O-.28 MR/HR
                                                                      .2S-.4 MR/HR
                                                                        .4-1 MR/HR
                                                                        1-2 MR/HR
                                                                        2-4 MR/HR
                                                                        4-5 MR/HR
Figure 2.  Reactor Test ground deposition pattern for Phoebus IB, EP-IV
           24 February 1967.  Discussed on Page 4.

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A comparison of Figures 1 and 2 shows that the particle ground

survey was generally performed in the area of highest deposition.

Thus, although the ground survey primarily determined the down-

wind distribution rather than both downwind and crosswind, it is

felt that it should be reasonably representative of the particle

hotline.  An exception is the points at less than about 25 miles from

the test cell, where our surveys appear to be generally east of the

hotline.  A composite of the studies indicates the debris hotline
                                   1O*3
was on an azimuth between 5 -  10  .  '  '    It appeared to start

NNE and "back" more northerly with distance.  Using ESSA/ARL

upper level weather data (radar) collected at 1430 on February 23,  1967,

over Jackass Flats, Nevada, an attempt was made to determine the

initial height attained by the particles.  The hodograph (Figure 3)

shows that a particle hotline of 7  would correspond to an  effective

release height of 10, 500 feet MSL and mean layer wind speed of

about 12 mph.


A.  Particle Concentration with Distance


    The number of particles detected on the  ground per  100m2 as a

    function of distance is  presented in Figure 4.  The indicated line

    is based on regression or least squares  analysis of  the data

    (log-log).  Only those sampling points near the hotline (as

    indicated by this study, the Pan American study, and  other

    effluent studies) were used in this analysis.  Fourteen of the

    21 sampling points were used.  The slope of the line is -2. 5 and

    the correlation coefficient for the indicated line is -0.95 or

    between -0.83 and -0.98 at the 95% confidence level. *
#The correlation coefficient squared is an indication of the  percent
of the variation of the data explained by the regression line.

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      DATA FROM ESSA/ARL
  23 FEB 67
  (3430 MSL) 1415

  Vector Plot of Winds by 1OOO ft.
     Height Increments

  Discussed on Page 7
                                                         1O.5
             Indicates 8.5 x 1O3 ft. MSL
                                             19O/16
                                                8.5,
                                         190/13
     Indicates 19O° Azimuth at 13
     Knots Between  7.5-8.5 x 1O3 ft. MSL
                                              7.5
                                           17O/13
                                                6.5
                                              160/O7
                                                        5.5
                                                      22O/O8
Figure 3.   Hodograph for Jackass Flats, Phoebus  IB, EP-IV.

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                                                      PHOEBUS 1B EP IV
                                                  (Based on 14 Selected Plots

                                                     Near the Hot Line )
                                                  Discussed on Page 7
            10'
        102



DISTANCE (miles)
Figure 4.  Number of particles per 100m2 versus distance (miles).




                                            9

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B.  Particle Size Distribution
    The size frequency distribution for 109 of the particles js pre-
    sented as a bar graph in Figure 5 (numerical information in
    Appendix C).   This information is also presented on log proba-
    bility paper in Figure 6.  It appears to give a reasonable fit to
    a log normal distribution with a geometric mean of about 12u .
    The goodness of fit for this  distribution was checked using a
    Chi(X) squared test.   The calculated value of X2 (95%  confidence
    level) for 6 degrees of freedom was 8.9.   Thus the data appear
    to be reasonably described by a log normal distribution.  But,
    Figure 6 gives  some indication of a platykurtic bimodal distribu-
    tion.
    The bimodal characteristic  of the curve could be due to the
    presence of two or more distributions.  That is, a basic distri-
    bution of fairly large particles and a distribution formed from
    fractured particles.  If this is the case, it is felt that  the fractu-
    ring took place in the environment.
    It should be emphasized that correlations  of the data may be
    biased by collection techniques (easier to  find more active and
    thus  possibly larger  particles, collection  was over a period of
    time, etc.); terrain features; and especially the fragile nature
    of the particles which made them very susceptible to fracturing
    during transport, collection, and analysis.  Therefore it is
    possible that some of the particles were reduced in size, thus
    affecting any correlations.  Care was  taken in collection and
    handling (see Appendix A for methods) in an attempt to minimize
    these effects.   If several particles were found in one sample,
    they were assumed to be parts of a fractured particle  and ex-
    cluded from the sizing analysis.  Particles were collected with
                                 10

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PARTICLE SIZE (microns)
Figure 5.  Particle size distribution,  Phoebus IB, EP-IV.

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                                                           PHOEBUS 1B EP IV
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Figure 6.  Log probability plot of 109 particles (size in microns).

                                           12

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    a small amount of extraneous material and were handled with
    minimum contact in the laboratory, i. e., sieve techniques, etc.,
    were not used.
It is worth emphasizing the following points:
1.   A measured area was surveyed at each location.  The survey
    was performed using a survey meter  and traversing the area at
    one-foot intervals or less with the probe 6 inches or less from
    the ground.  All indications of particles  were noted.  Of a total
    of 228 indications,  about 180 particles were collected,  170 from
    monitored locations, 10 close-in where particles per unit area
    were not determined.  Of those picked up, about 15 were used
    in developing techniques  and are thus not reported in the sizing
    results.  Of the remaining  165 particles, 56 were noted to be
    fractured during sizing and thus not used in analysis of size.
    It is felt that the reduction  from the original  165 to 109 for
    sizing occurred in a random manner.  Where all the particles
    located in the measured area were not picked up, the choice
    was for the "hotter" ones.

2.  A cut-off in size (such as 10|o.) was not used.   That is, the actual
    size of all the  particles was determined  and reported.

3.  Even if the  65  unsized particles were included and were considered
    to be above the geometric mean determined (12|j.), the new
    geometric mean would be less than 20(0, .

Table 1 gives a  subdivision of the particles into several categories
based on size and the distance at which the particles were  collected.
                                13

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 Table 1.  Particle size distribution(microns).
Category
All particles;
at all distances
Particles > lOfj.
at all distances
All particles;
10 miles
Particles > 10(j.
< 10 miles
Particles > 10|JL
22-39 miles
All particles;
39-82 miles
Particles > lOu-
39 miles
No. of
Particles in
Category
109
59
43
28
13
17
9
Geometric
Mean
Diameter
12.2
25.7
14. 1
34.7
18.7
11.4
22
Geometric
Standard
Deviation
2.7
1.9
3.2
2.0
1.8
« M «
...
This breakdown into various size categories makes the results more
analogous to those of other study groups (Pan American and
Los Alamos Scientific Laboratory) which were based on analysis of
particles greater  than 10 - 15(j. in diameter.  '
C.  Radioactive Constituents of Particles
    Radiometric measurements were made on the  particles to
    determine beta plus gamma activity (open window GM probe),
    alpha activity, and specific nuclides.  The various radiometric
    measurements were not all made on the same  particles, there-
    fore,  they are not necessarily related.
    The beta plus gamma activity (GM probe) of 78 particles, along
    with their size (Feret diameter), is given in Appendix D.  The
    distance downwind from the reactor, where they were found, is
    also indicated.  This gross activity is  only a relative number,
    and is reported as counts per minute detected  by the GM probe at
                                14

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time of count.  The particles were all counted at about the same
time (5 days after the event).  The probe used has  an approximate
efficiency of about 10% for beta and less than 1% for  gamma
activity.
The alpha activity of eleven of the particles was measured on a
NMC  PC-3B counter and ranged from approximately 0. 1 to
28 pCi/particle with an average of 8 pCi/particle.
The specific isotope analysis, based on gamma spectroscopy
using aNal(Tl) 4-by 4-inch crystal, for a number of particles is
indicated in Table 2.  Several particles were analyzed on a
germanium (Li) detector. The germanium detector was not
calibrated for quantitative analysis,  thus the results were used
only to help confirm the "Nal analysis. "
The results in Table 2 are based on hand analysis by the Compton
subtraction method,  including the use of half-life verification,
of the gamma spectra.  In some of the samples reported in
Table 2, more than one active particle was found.  In these cases
it is not known whether each particle was deposited separately
or if they resulted from a single  particle which was fractured
by handling, but the latter appears more likely.  In addition to
the results in Table 2, the spectrum from the germanium
detector indicated the presence of 31 Th (daughter  product of
235 U).  Short half-life isotopes noted to  be present,  but not
quantitated were  91Sr,  9Z Sr, 92 Y and 135I.  Other fission
products were undoubtedly present, but below the level of detecta-
bility.  A least squares spectrum stripping computer program
was used to analyze 14 of the particles.  The results were similar
to those in Table 2.
                            15

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Table 2.  Results of isotopic  analysis of particles (pCi)
Sample
No . '• •:
95 Zr
97 Zr
99 Mo
103Ru
132 Te
13JI
140Ba
141Ce
143Ce
147 Nd
2"Np
Total

20528
A
ND
ND
S4.000 110
ND
8, 200 7
ND
150,000 110
78,000 67
ND
ND
ND
320,00') 290

B
ND
ND
, 000
ND
, 500
ND
, 000
, 000
ND
ND
ND
,000

A
2, 500
240, 000
12,000
ND
3, 000
ND
1,600
2,800
8, 500
3, 000
51, 000
320, 000
ffll.Sr '2 Si
20540
B
15, 000
ND
18, 000
5, 500
8, 000
ND
15, 000
210, 000
7, 100
26, 000
470, 000
770, 000
• 92 7 . 97 7.
c
110, 000
8, 600, 000
540, 000
ND
71, 000
ND
60, 000
100, 000
280, 000
210, 000
1, 300, 000
1 1, 000, 000
r 9'Mo 132T
20542
A
1, 100
B
2, 000
93,000 180,000
1,700
ND
1, 100
ND
2, 200
1, 500
3,400
1,800
10, 000
120, 000 2
135, 140B,
6, 200
1, 100
3, 000
ND
4, 900
3, 300
8, 200
5, 000
35, 000
50, 000
141 CP
20543
12,000
1, 900, 000
280, 000
2, 000
2, 600
1, 000
ND
300
2, 500
ND
ND
2, 200, 000
143 OP 147Nri
20544
18, 000
1, 100, 000
180, 000
ND
12, 000
ND
24, 000
240, 000
61, 000
47,000
120, 000
1, 800, 000
239Nn
A
3, 500
330,000
4, 500
6, 300
4,400
ND
7,400
5, 500
14,000
6, 500
50, 000
430, 000

20545
B
5, 300
880,000 2,
11, 000
24, 000
3, 700
ND
20, 000
17, 000
11,000
8, 300
120, 000
1, 100, 000 2,

C
18, 000
000,000
350, 000
ND
8,700
ND
81, 000
27,000
82, 000
31, 000
210,000
800, 000

D
23,000
2, 100, 000
74, 000
55,000
16, 000
ND
60, 000
53, 000
92, 000
57,000
220, 000
2,800, 000

20546
34,000
2, 600, 000
88,000
ND
16, 000
ND
64, 000
9, 600
110,000
61, 000
180,000
3, 200, 000

    pie  #20623-1- Indications of 95Zr,  97Zr,  99Mo,  140Ba, UICe, 14JCe, 147Nd, 239Np



    pie  #20623-2- Indications of 95Zr,  97 Zr,  99Mo, 140Ba,  141Ce,  143Ce,  l47Nd, 239Np



    rapolated to 1515 PST,  February 23, 1967



    phabetic letters (A, B,  etc.) indicate a subdivision of the sample




   - Not detectable

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    Comparison of the results in Table 2 shows that the two
    portions of sample 20528 have similar inventories of fission
    products and are dissimilar to all other samples, indicating
    that they did result from fractionation of a single particle (note
    page 32, microprobe analysis indicated a possible difference.)
    The similarity in inventories of  20540-A and C indicate the
    same; however,  20540-B is unlike A and C, which would  tend to
    show  that this was not a part of the original particle or that the
    original particle may have  been  a combination of several types
    of material.  This might be explainable by a combination of
    reactor material (UC_ and/or graphite) and environmental dust.
    The gamma spectra from 20542-A and B indicate that these
    probably originated from one particle.  Inspection of 20545
    indicates that portions A, B and D are similar,  but that portion
    C  is different.   Because of the low density of particles on the
    ground, it is difficult to conceive of more than one particle being
    picked up in a sample (taken from an area of about one square
    inch).  Thus, the hypothesis of heterogeneous particle compo-
    sition is presented.
    Radioisotope analysis indicated a significant amount of fraction-
    ation (discussed in Appendix F).

D.  Correlation of  Particle Size, Gross Activity and Distance
    A  number of attempts were made to correlate the parameters  of
    particle size, gross activity and distance.
    Both regression analysis and correlation  coefficients were used
    on various transforms of the data (linear, log linear,  and log log).
    The results of the various correlation attempts are given in
    Appendix E.  The correlations best justified by theory are given
    in Table 3.  The premises used were:
    1.   Regression is generally used where one of the variables is
                                17

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Type
Data Correlation
Size and
Distance^
Activity2
and Distance
Activity
and Size
Log Log

Log Log

Log Log
Linear
Number of
Data Points
6

6

68
68
Slope of Correlation
Line4 Coefficient
-0.2 -0.641
(See Fig.
-0.4 -0.711
(See Fig.
-0. 171
-0.46

7)

8)


1.  Not significantly different from zero at the 95% confidence level.
2.  Radioactivity as determined by a GM probe.
3.  Distance from test cell at which particle was found.
4.  Parameter =  •f (Distance)11 where n is reported slope.

         assumed to vary with the other, i. e. , size with distance.
         Correlation coefficients are applicable for two variables
         which are both random, but are assumed to vary together,
         e.g.,  size and activity.  The correlation coefficient may
         also be used to test the goodness of fit of a regression line.
         That is, the correlation coefficient squared is the fraction
         of variance in the data explained by the regression line.
    2.   The log log correlations are reported because the variables
         are assumed to be related by power functions, e.g. , activity
         is a function of the surface area (r2) and the volume (r3) of
         the particle and the distance traveled is a function of termi-
         nal settling velocity(r 2).  Thus a log log plot would be  a
         straight line where graphs of other functions of the data would
         be expected to be curves.
    3.   The particle size and activity are described by a distribution
         rather than a precise value  at each distance.   Thus, the
         geometric mean of size and activity for various distance
         increments was used in the  correlation attempts.  The
                                 18

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    geometric average size and activity were determined for
    the distance intervals:  7, 9, 22-26,  29-34,  39-44, and
    51-82 miles. The separation into intervals was necessary
    to obtain a reasonable number of particles for each distance.
    The averages were then plotted at an average distance
    (weighted by number of particles at the various distances).
The geometric mean for particle size is plotted versus distance
in Figure 7-  The line is based on a regression analysis.  The
correlation coefficient for the indicated size with distance
relation (mean size  = distance to the minus 0. 2 power) is  -0. 64.
Due in part to the small number of points used in the correlation,
this is not significantly different from zero at the 95% confidence
level,  but although the precise relation is in doubt,  there  appears
to be a relationship  between size and distance.
The correlation coefficient for the regression line (Figure 8) for
activity of particle versus distance is -0.71.  This indicates a
reasonable fit of the data,  but due to the limited number of points,
it is not significantly different from zero at the 95% confidence
level.   However,  it  definitely  suggests a decrease in activity
with distance.
It is difficult to explain the correlations of activity (P + Y) with
size.   The activity should  be a function of the area or volume of
the particle (radius  squared or cubed),  so a log log  plot should
give the best straight line.   However, the linear  relationship is
stronger than the log log relationship.   Thus, they are both
reported in Table 3.  This may in part be due to  the use of a
GM probe for the radioactivity measurement.  Beta and gamma
efficiency for the probe, resolving time (about 10% or more),
and energy dependence were not considered.
                             19

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     102
   
-------
     101
   I-
   u
   <
   UJ
   _l
   o
   h
   g
   <
   Q.
   UJ
  UJ
      10°
     1O
                        i—i—rrr
                  T—I—T~TT
   PHOEBUS 1B  EP IV


Discussed on Page i g
                                                        SLOPE = -O.4

                                          CORRELATION COEFF. = -O.7
                                                                   J	III!
                                    10'


                              DISTANCE FROM TEST CELL (miles)
                               102
Figure 8.  Survey meter readings of particles versus distance from test cell

           (beta + gamma with G.M. instrument).
                                         21

-------
    Figure 9 gives an indication of the distance downwind ve
    size particles can be transported.  The figure is based on:
    1.   Stokes1 Law settling velocity.
    2.   Release height of one  mile,  i. e. , difference between release
         height and ground level at point of deposition.
    3.   Wind or transport speed of 15 mph.
    Atmospheric diffusion or turbulence was not considered,  but
    would primarily cause the deposition to be spread (distance
    plus and minus) around the indicated transport distance.

E.  Elemental and Chemical Composition
    A number of samples were analyzed with an electron micro-
    probe to determine their elemental and chemical composition.
    All the particles were not  analyzed, but those selected should
    be generally representative of most of the  particles collected.
    These results are given in Table 4  and the general sample de-
    scription is given in Table 5.
    Three particles were analyzed for quantitative results.  Quanti-
    tative analyses  of one bead yielded the following results:
                  Element             Percent by Weight
                  Uranium                  91.0
                  Carbon                    8.4
                  Oxygen                    0.7
    The other results were similar,  i.e. ,  +  10% of the given value.
    These elemental fractions indicate  a stoichiometric composition
    of about 90% of  uranium as UC  and about 10% or less as UO
                                 ^                             2
    One particle was analyzed by X-ray diffraction subsequent to
    microprobe analysis  (U, C, and  O). The particle was removed

                                22

-------
      102
                Basis:  15 mile per hour wind speed.
                       Stokes' Settling Velocity for
                          Streamline Motion

                Lines:  A. Center Line
                          Release height 1 mile above terrain.
                          Particle density of 11  g/cm3


                       B. Center Line
                          Release height 1  mile above terrain.
                          Particle density of 5 g/cm3

                       C. Center Line
                          Release height % mile  above terrain.
                          Particle density of 11  g/cm3
                                                   J	I	I	L_L
         10'
                               DISTANCE FROM TEST CELL (miles)
Figure 9-   Estimated downwind transport distance for various size particles,
            Discussed on page 22.
                                            23

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Table 4.  Results of electron microprobe analysis
Sample No. *
    Microprobe Results
                                                    Comments
20528-A
20528-B
20540-A


20540-B

20542-A


20542-B

20543

20544


20545-A
No detectable U, Zr, Mo, Nb
4 hot spots on this sample

(1)  Contained U and C
     No detectable Zr,  Mo,
     Nb or O

(2)  Contained U and C
    Indications  of traces of
    Nb and O
    No detectable Zr or Mo

(3)  Contained U and C
    No detectable Zr, Mo,
    or Nb

(4)  Contained U and C
    No detectable Zr, Mo,
    or Nb

No detectable U, Zr, Mo, or
Nb
Silicate matrix, disintegrated
under electron beam.

Particle lost in transfer
No detectable U, Zr, Mo, or
Nb
Contained U and C
Indications of trace of Nb
Contained U and C on silica
matrix

Sample  could not be analyzed
because the activity was on a
large grain of sand.
Radionuclide anal-
ysis indicated A &
B were similar.
Radionuclide anal-
ysis noted dissimi-
larity.
Radionuclide anal-
ysis similar for
A & B.
                                                 Radionuclide anal-
                                                 ysis noted A & B to
                                                 be similar,  but C to
                                                 be different from
                                                 A & B.
                                 24

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Table 4.  Results of electron microprobe analysis (continued)

Sample No. *        Microprobe Results            Comments

20545-BContained U, C,  and O
                 No detectable Zr, Mo,
                 or Nb

20545-C         No detectable U, Zr, Mo,
                 or NB

	         Contained U, C  and O

	         Contained U, C  and O

                 Contained U, C  and O
*See Table 5 for collection location,  size and gross activity.
                                25

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     Table 5.  Location,  size, and total isotopic activity of particles
N)
Sample No.
20528
20540
20542
20543
20544
20545
20546
20623
Azimuth -Distance
357°
3°
16°
16°
12°
13°
13°
9°
6.
21.
25.
25.
23.
23.
23.
72.
0 mi
5 mi
0 mi
0 mi
5 mi
0 mi
0 mi
0 mi
Size (p. ) Activity*
45 x 32** 610,
16 12,000,
2x3
20 x 24 370,
19 x 24
9 x 14 2, 200,
1,800,
7,100,
3, 200,
15
(PCi)
000
000
000
000
000
000
000
Comments




Many <
One 25
One on
Several
One on




6n
x 20|j.
a grain of sand
grain of sand
>25 active pieces
     :'':Total identified activity to two significant figures.  See Table  2 for specific isotopic activity.
     ## The two figures indicate the dimensions of the particle  as  seen in a plane view.  A single
       figure indicates uniform dimensions.

-------
    from its mounting with a micro-manipulator causing it to fracture.
    A fragment of the original particle of approximately eight microns
    in diameter was mounted on a pyrex glass fiber and placed in a
    Debye-Scherrer powder camera. Forty-foui1 hours of exposure
    produced very faint but readable diffraction lines.  The relative
    line intensities  could not be measured;  however, line positions
    were determined.  The diffraction pattern of the sample was
    directly compared with those from a reactor bead and spectro-
    graphic grade carbon.  The diffraction  analysis indicated only
    uranium carbide and free carbon to be present.  Uranium oxide
    would not be detected in this particular  analysis because of the
    low concentration of uranium oxide in the sample and the small
    sample size.
    The free carbon that was indicated in the  diffraction analysis is
    probably due to carbon deposition on the sample during the micro-
    probe analysis.  Correlation of these analyses indicated that the
    particle was composed of UC, and a form of uranium oxide.  The
                                L*
    uranium oxide was probably UO .

F.  Particle Density
    Density determinations were made on 8 particles (see  table 6).
    The arithmetic  mean density (also geometric mean) was
    11  gm/cm3.  The determination was based on the equivalent
    diameter (based on two dimensional projection of a spherical
    particle of equal cross sectional area) and Stokes1 settling
    velocity in hexane.  The method Is further described in Appendix A.
                                 27

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Table 6.  Density of particles
Equivalent Diameter
(n)
28
25
20
18
22
20
12
20
Density
(gm/cc)
9.59
13.20
9.79
11.56
11.53
12.88
11.43
8. 11
G.  Biological Clearance Rates
    A study was performed to estimate the clearance rate in rats
    for particles collected from the reactor run.  The objectives
    were as follows:
    Primary   - Establish methodology for future studies.
    Secondary - Obtain an indication of clearance times  and routes
                and the solubility of the radioactivity associated
                with the particles.
    Due to the limited number of radioactive particulates available
    for this study,  only two rats were injected; one intratracheally and
    the other  intraesophageally. Particulates with a CMD*of less
    than 10n  were  suspended in an aqueous solution and 0. 15 ml of the
    suspension was injected into the trachea (lungs)  of one rat and
    into the esophagus (stomach) of the other rat.
    Clearance from the animal injected by the intraesophageal route
    (stomach) was rapid.  Thirty-five percent of the original body
    burden cleared in the first 24-hour period and an additional
    *Count mean diameter.
                                28

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fifty-eight percent of the original burden cleared in the second
24-hour period.  The amount remaining after the fifth day was
insignificant.
Clearance was much slower and relatively constant for the
animal injected by the intratracheal route.  A clearance half-
time of approximately 20 days was calculated for this  animal
with over 10 percent of  the original body burden still remaining
66 days following injection of the radioactive material.  This
animal is still under observation and will be permitted to expire
naturally.  The results  indicate that these particulates were
relatively insoluble since essentially all the radioactivity lost
in both rats was accounted for in the feces.
                             29

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               III.  SUMMARY AND CONCLUSIONS

The objectives of the program were intentionally limited so that a
reasonable degree of success could be accomplished with available
personnel and financial resources.  Thus, although there is reasonable
doubt remaining concerning some of particle parameters and many
questions to be answered or investigated more fully in the future,
it is felt the objectives outlined in Section 1  - B were met.
Post-run inspections  of the reactor  cores have shown varying types
of corrosion both with type of reactor,  i. e. ,  Phoebus or NRX (KIWI),
and with reactors within a type, i.e. , NRX-A4 or  A5.  Thus, knowledge
of the parameters of  particles in the effluent from a given reactor
test may not be directly applicable to other reactor tests.
It should be reiterated that this  report,  and therefore the conclusions
drawn from it, are based on a limited amount of information.  Thus,
the following observations should be used with discretion and should
be validated with future reactor tests.

Observations
A.  A least squares fit of the data indicated that the particle concen-
    tration per unit area on the ground decreased with distance to
    about the 2. 5 power (Figure 4,  page 13).  In addition to indicating
    the change with distance, an estimate of particle concentration on
    the hotline is indicated.  There was very little  wind shear for
    the Phoebus  IB, EP-IV,  and a moderate wind speed.  Thus the
    figure should give a reasonable indication for reactor runs of
    this type in the future  (same power,  power integral, and fuel
    type).
                                 30

-------
B.  The average particle  size and activity decreased with distance.
    The data'are insufficient to denote a definite relationship,  but
    indicate the decrease with distance is less than distance to the
    first power (see Figures 7 and 8).

C.  The overall size distribution of the particles collected from
    6 to 82 miles (based on sizing 109 particles) gave a reasonable
    fit to a log normal distribution.  This distribution had  a geo-
    metric mean of 12u and geometric standard deviation of 2. 7.   A
    breakdown of the distribution into those particles equal to or
    greater than 10(0.  collected at less than 10 miles gave a geometric
    mean of 35(0. with a geometric  standard deviation of 2.

D.  Based on the average density for eight particles  (11 g/cc - which
    may not be representative of all particles) and the considerations
    of aerodynamic diameter, greater than 90% of the particles
    detected were  above an aerodynamic diameter of 10(j. which is
    usually considered the upper size level for penetration into the
    respiratory system.  This statement holds for all downwind
    distances where particles were detected.  Admittedly insufficient
    particles were detected to determine more than  an indication of
    particle size with distance,  especially beyond 50 miles.

E.  Based on eleven randomly selected particles analyzed  for elemen-
    tal composition it is concluded that the particles collected  were
    primarily uranium and carbon.  The density results also indicate
    the particles are largely uranium.. It is suggested,  based  on
    other reports  *»  '  that the particles might fall  into two types
    of distributions, i.e., large particles around 100(j.  maybe UC~
    with associated graphite coat and  possibly natural environmental
    material, and  the small particles primarily UC?.   Some of the
                                  31

-------
    particles were noted to be small UC, particles associated with
    silicate material (material from the natural environment).

F.  There appears to be a "weathering" effect in detecting and col-
    lecting the particles. The particles collected  beyond 40 miles
    from the test cell were primarily collected on the  26th or 2 to
    3 days after the near-in collections.  From Figure 7 it can be
    noted that particle size did not decrease as much with distance
    as might be  expected (based on Stokes1 law).  This could be
    explained if  the small particles were no  longer detectable at the
    time of survey.  Also (Figure 4) the observed  particle concen-
    tration on the ground fell off slightly faster than might be ex-
    pected.  This would follow the previous reasoning in that the
    small particles were not detected,  at least not with the same
    efficiency as the larger particles, at the later  survey times.

G.  As can be noted from Figures 1 and 2, particles were deposited
    in the off-site area (out to 82 miles from the test cell).   But,
    the deposition density was of the magnitude of  1 per 100m2 and
    was in areas of very low population density.  The only people  in
    an area of known deposition were at Diablo (3 people).  There
    was no known case where the general population came in contact
    with this effluent.

H.  Due to the variation in distance to the off-site  boundary and
    variation in  population density in the off-site area, it is difficult
    to assess the potential hazards from these particles.  This
    would be true even if the hazard resulting from human interaction
    with the  particles was known; which is not the  case.  With the
    unknowns, it becomes impossible to make a definitive statement
    at this time  concerning the hazard in the off-site area.  Among
                                 32

-------
the statements that can be made concerning the potential
hazard of these particles are:
1.   Particles were transported to 82 miles.
2.   The ground density of the particles and thus the probability
     of human interaction (disregarding population densities)
     decreases with distance to about the 2. 5 power.
3.   The particles contain microcurie quantities of fission products,
4.   The biological half-life in the lung may be very long.
                             -33

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                          REFERENCES

1.   "Preliminary Report of Off-Site Surveillance for the
    Phoebus-IB Test Series," Public Health Service, Southwestern
    Radiological Health Laboratory, March 9,  1967.
2.   "Phoebus IB,  EP-IV Effluent and Ground Deposition Surveys,"
    EG&G,  Inc.; 21 April 1967; EG&G 1183-1321.
3.   Van Vleck,  L.  D. , "Summary of Results,Effluent Monitoring,
    Phoebus IB, EP-IV, " PAA 33-12, 19 July  1967.
4.   Bolles, R. C. and  Ballou, N. E. ,  "Calculated Activities and
    Abundances of 235U Fission Products," USNRDL-456.
5.   Altomare, P.  M. and Coleman,  J. R. ; "Study of Particulate
    Effluent from  Nuclear Rocket Engine Test." Part 1, NUS
    Corporation, September 1967.
6.   McNelis,  D. N. ,   Memo to Dr.  D. S.  Earth,  Chief, BER,
    SWRHL, on 10/18/66.
                                 34

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                        APPENDICES


APPENDIX A.  METHODS OF COLLECTION AND ANALYSIS     35

APPENDIX B.  PARTICLE SURVEY RESULTS                  41

APPENDIX C.  FREQUENCY OF PARTICLE SIZE              44

APPENDIX D.  SURVEY METER READINGS OF PARTICLES     46

APPENDIX E.  PARTICLE SIZE,  ACTIVITY AND DISTANCE
              CORRELATION COEFFICIENTS                48

APPENDIX F.  ISOTOPIC FRACTIONATION                   49

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                           APPENDIX A
           METHODS OF COLLECTION AND ANALYSIS

A.  Particle Collection
    Particles were located by monitoring teams surveying either an
    area of 300 square feet or 100 square meters  (except as noted
    in Table 1) with an Eberline E-500B Geiger counter with the
    shield open (beta plus gamma) and/or a Precision 111 "Scintil-
    lator."  The general area to be surveyed was  determined from
    the results of aerial  cloud tracking,  gamma exposure measure-
    ments during cloud passage, and gross gamma counting of
    vegetation results from two on-site vegetation arcs and an arc off-
    site on Highway 25 (Figure 1).  Collection took place  over a six-
    day period.  The surveys were performed along a downwind
    sector from  about 350° to 30°  and between 9 and  115 miles.
    Fifty-three areas were surveyed (see Figure  1).   Particles were
    collected with as little  soil as  possible.  It is  felt that the col-
    lection techniques were reasonably  good,  but by no means
    absolute.  Out of the 228 indications for particles, about 170 par-
    ticles were picked up (no attempt was made to pick up all of them).
    Where all the particles were not picked up, the "hotter" ones
    were  selected.  Various numbers of these particles were then
    used in the different  analyses.
    One particle  was collected by impaction on sticky material placed
    on the leading wing edge of the PHS sampling  aircraft.  The
    location of collection of the particle could not  be  defined because of
    the method of collection.
                                35

-------
    The particles were isolated from the  sampled material, usirig
    microscopy, autoradiography, and collimated PA detectors.
    They were fixed on glass slides with polyvinyl chloride (PVC)
    or saran film. After fixing on the slide, particles were auto-
    radiographed (except for 5  of them) to determine which was  the
    actual particle.  In some samples more than one particle was
    found.  The particles were  extremely fragile and so in these
    cases it is not known whether samples were fractured through
    handling or were deposited as several particles.  When more
    than one particle was noted in the sample,  it was excluded from
    the sizing results. Less than 1/3 of the particles sized were
    excluded because of fracturing.

B.  Particle Sizing
    The diameter was determined using the Feret diameter measure-
    ment.   A qualitative determination to establish that the third
    dimension was of the same  regularity as the other two was made
    by focusing alternately on the topmost portion of the particle and
    on its lowest maximum dimension.  The particle dimensions
    were irregular, but were more spherical than "needle like."

C.  Constituent Radioactivity of the Particles
    Three types of radiometric measurements  were performed.
    They are as follows:
    1.  Gross (3 + \  - Particles were counted approximately 5  days
        after collection using a RM-3A GM (open window) detector.
        The detector was not calibrated,  but probably has about 10%
        and less than 1% overall  efficiency respectively for beta and
        gamma.  Results are given in CPM at time of count.
                                 36

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2.   Alpha Activity - Alpha activity was measured on an
    NMC PC-3B counter.   Eleven particles were  analyzed.
    Activity is reported in pCi/particle as of time of count.  No
    correction was made for self-absorption.  Thus, in reality,
    the activity reported is probably surface activity rather than
    total particle activity.
3.   Specific Isotope Analysis - Quantitative specific isotope
    analysis was performed by gamma spectroscopy. Spectra were ob-
    tained by using a 4- by 4-inch Nal(Tl) crystal, a 4-inch photo-multi-
    plier, and  200 channels of a 400-channel pulse height analyzer.
    Analysis was performed from 0-2 MeV at 10  keV per
    channel. Spectra from a lithium-drifted germanium diode
    detector in connection with a 1024 channel analyzer were
    used in analysis but were not quantitated due to lack of
    qualitative  calibration of the instrument.
    These results were analyzed by two techniques - Compton
    Subtraction and weighted least squares computer program.
    COMPTON SUBTRACTION
    Spectra from several recounts were used with this method,
    thus utilizing half-life  determinations for the various gamma
    peaks to confirm the analysis.
    LEAST  SQUARES PROGRAM
    A computer program based on a weighted least squares
    analysis was used.  The weighting function was based on the
    counting error in each channel.  The number of isotopes
    that  can be used in the computer program is variable,  but it
    is limited to  isotopes where standards are available.
    Standards for the following isotopes were not available for
                            37

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        the computer program:  91Sr,  92Sr, 92Y, 135I, 97ZrNb, and
        143Ce.  Gamma spectra taken about 2 weeks after the reactor
        run were used for the analysis,  The  previously mentioned
        isotopes would have decayed to one-thousandth or less of
        their original activity by this time.

D.  Correlation Coefficients
    Linear  correlation coefficients were calculated for both the
    untransformed data and logarithmic transforms (transforms are
    an attempt to make the data fit a straight line - the correlation
    coefficient is a measure of the fit to a straight line).  Particle
    size and activity are distributed at each distance.  Thus,  a
    point by point correlation, e.g. , parameter of particle versus
    distance at which it was found is misleading. Thus, these cor-
    relations  are based on the mean of the  parameter at each dis-
    tance.  The correlation for particle size and activity was done
    on a point by point  basis.

E.  Elemental Chemical Composition
    Chemical composition was determined  by  electron microprobe
    (Norelco Instrument) analysis.  In this  process, the character-
    istic X-rays from electron excitation are  passed through an
    X-ray energy dispersing crystal to a detector.  Normally, an
    emission angle from 30 to 70 degrees is measured with a
    rotation of 2 degrees per minute.   The  signal and associated
    angle are recorded on a strip chart recorder.  Due to the large
    number of particles to be analyzed, in most cases,  just the
    spectral peaks for the various  elements were measured.  The
    particles  were analyzed for U,  Zr, Mo, Nb, C and O.  The
    area of the electron beam used on these samples was approxi-
    mately  one micron. The minimum detectable quantity of
                                38

-------
    U, Zr,  Mo and Nb was approximately 10~12 grams regardless
    of beam size, providing that the beam remained entirely on the
    particle.  The minimum detectable limit is significantly greater
    for elements of low atomic weight such as  O and C.
    The  small beam size was used on all particles to ensure that
    the beam remained on the particle being  examined.  Some
    larger particles were also  examined with a larger beam, approxi-
    mating the particle size, to determine if detectable amounts of
    the elements sought were spread over the entire surface.
    The  most conclusive semi-quantitative analysis of uranium and
    carbon was  accomplished by comparing the samples with a
    crushed reactor bead mounted by the same procedure that was
    used on the  samples.  The  relative uranium-carbon count rate
    ratios were used for comparison with the data from the sample.
    The  oxygen content was quantitated by comparing the uncorrected,
    net count rate of the  oxygen in the sample with the oxygen count
    rate from ruby (Al_0 ).  The usual mathematical corrections used
                       £•  j
    for quantitative probe analysis could not  be used because mass
    absorption coefficients and fluorescence  corrections are not
    available for carbon and oxygen.

F.  Density of Particles
    The  density of eight particles (12 - 28|o.  in size) was estimated by
    use of Stokes1 Law and the  settling velocity through hexane
    (viscosity = 0. 326 cp).  The equivalent diameter was taken to be
    that of the two dimensional projection of  a  spherical particle of
    equal cross sectional area. The determination of equivalent size
    was  done on a Zeiss  Particle Size Analyzer.  A measure of the
    accuracy and reproducibility of this procedure was made by
    using 27.4|jL  silver spheres in the same  experimental arrangement.
                                 39

-------
    Ten of these spheres were allowed to fall 15. 24 cm in hexane

    and their terminal velocities were recorded.  The average

    settling velocity was 1. 28 cm/sec with a range of from  1.21-

    1. 34 cm/sec.  Based on the average measurement, a density

    of 10.8 gm/cc was calculated for the  silver spheres (pure

    silver has a density of 10. 5).  Inaccuracies caused by irregu-

    larities of particle dimensions would  tend to give  a low  rather

    than a high density using  the  settling velocity technique.


G.  Biological Clearing  Rate  of Internally Deposited Particles
    for Rats

    A preliminary biological  experiment was performed with rats.

    Particles with a CMDvof less than 10|j. were suspended in an

    aqueous  solution and injected in two rats; one by the intra-

    tracheal route and the other intraesophageally.  The main

    objective of the study was to  establish methodology, with

    secondary objectives of obtaining gross indications of clearance
    times  and routes and particulate solubility in biological  fluids.

    Following the injection, each animal was placed in a restrainer
    between the 9-inch opposed sodium iodide crystals and whole-

    body counted.  This procedure was repeated daily on each rat
    until the detectable activity dropped to less  than 50 percent of

    the original body burden.  At this point, the counting frequency

    was changed to a weekly schedule and maintained at this rate

    until significant counts were no longer obtained.  In addition

    urine and fecal eliminations were collected from each animal

    and  counted at the same counting frequency as that utilized for
    the whole-body count.

    *Count mean diameter.
                                 40

-------
       APPENDIX B



PARTICLE SURVEY RESULTS
Date of
Collec-
tion
February
1967
23






24









25




Distance
from Test
Cell "C"
in Miles
9
11
14
17
19
30
50
19
21.5
23
23. 5
24
25
26
26
29
34
65
66
69
72

Azimuth
from Test
Cell "C"
in True
Degrees
20
30
20
30
20
30
20
355
3
13
12
27
16
7
10
8
7
18
21
10
9
(41)
Number*
Parti-
cles
per
300 ft2







1 c »'* »'*
J, 3 -i- ~f
16**
16
16
0
4




0*ln »'- *'*
1* "I* ff
0
o * * *
l#*f ***

Number
Parti-
cles
per
100 m2
225****
0
15
0
3
0
0
54
57
57
57

14
5
12
12
6



4


-------
             APPENDIX B
PARTICLE SURVEY RESULTS (continued)
Date of
Collec-
tion
February
1967
26







27 & 28














Distance
from Test
Cell "C"
in Miles
39
44
51
60
67
74
82
82
92
92
93
93.5
95
87
76.5
74
72
70
112.5
113
113.5
114
114.5
Azimuth
from Test
Cell "C"
in True
Degrees
5
4
5
7
4
0
356
356
6
7
9
10
11
7
8
8
9
10
3
2
1
0
359
Number* Number
Parti- Parti-
cles cles
per per
300ft2 100m2
4
7
6
4
5
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
                  (42)

-------
                          APPENDIX B

            PARTICLE SURVEY RESULTS (continued)
Date of
Collec-
tion
February
1967
27 & 28
(cont'd)







Distance
from Test
Cell "C"
in Miles
115. 5
115.5
93.5
93. 5
93. 5
94
94
95
91
Azimuth
from Test
Cell "C"
in True
Degrees
358
357
356
357
359
0
1
2
5
Number* Number
Parti- Parti-
cles cles
per per
300ft2 100m2
0
0
0
0
0
0
0
0
0
#The area surveyed was 300 ft  for indicated results in this column
and 100 m2  for other results.  Results were then normalized to
100 m2  and included in the next column.
**P + Y contact readings for E-500 B GM survey instrument at time
of collection.
   Particles at 19 miles         1 particle  > 200 mR/hr
                                2 particles   100 - 200 mR/hr
                                3 particles    50 - 100 mR/hr
                                9 particles <  50 mR/hr

   Particles at 21.5 miles       4 particles > 100 - 200 mR/hr
                                1 particle      50  - 100 mR/hr
                               11 particles <   50 mR/hr

   Particle  at 72 miles          1 particle      10-50 mR/hr

***Area surveyed was approximate.
#*##An area of about 35m2  was surveyed and 78 particles detected
     and picked up.
                                43

-------
          APPENDIX C
FREQUENCY OF PARTICLE SIZE
Size (|j. )
2
3
4
5
6
7
8
9
10
13
15
16
17
18
19
20
21
23
25
26
27
28
30
Frequency
3
7
6
12
9
3
5
5
6
3
2
6
2
5
1
2
4
2
1
1
1
2
1
% Frequency
2.8
6.4
5.5
11.0
8. 3
2.8
4.6
4.6
5.4
2.8
1.8
5.5
1.8
4.6
0.9
1.8
3.7
1.8
0.9
0.9
0.9
1.8
0.9
Cumulative %
< Stated Size
2.75
9. 18
14.7
25.6
34.0
36.7
41.3
45.9
51.3
54. 1
56.0
61.5
63.3
68.0
68.9
70.6
74.4
76. 1
77. 1
78.0
79.0
80.8
81.7
              44

-------
                APPENDIX C
FREQUENCY OF PARTICLE SIZE (continued)
Size (a )
32
33
40
45
46
47
48
50
51
52
58
60
78
81
83
115
144
Frequency
1
1
2
2
1
1
1
1
1
1
1
1
2
1
1
1
1
% Frequency
0.9
0.9
1.8
1.8
0.9
0.9
0.9
0.9
0.9
0.9
0.9
0.9
1.8
0.9
0.9
0.9
0.9
Cumulative %
< Stated Size
82.6
83.5
85.4
87.2
88. 1
89.0
90.0
90.8
91.9
92.6
93.6
94.5
96.4
97.3
97.2
99.1
100.0
                     45

-------
              APPENDIX D



SURVEY METER READINGS OF PARTICLES
Distance
(Miles)
6**
7**
7
7
7
7
7
7
7
7
9
9
9
9
9
9
9
9
9
9
9
9
Size
(n)
40
6
19
13
40
32
7
26
30
18
23
7
33
20
3
9
3
60
7
45
5
83
P + Y
Activity*
(cpm)
NM
14,000
25,000
3, 100
600
3, 100
1,400
1,400
3,800
2,500
2,900
9,000
20,000
700
5,500
1,900
8, 500
14,000
3, 200
10,000
2,700
24,000
Distance
(Miles)
9
9
9
9
9
9
9
9
9
9
9
9
22.5
25
26
26
26
26
26
26
26
26
Size
(Ji)
5
78
6
9
10
3
78
28
144
5
4
3
16
13
6
5
18
3
47
10
9
10
P + Y
Activity*
(cpm)
3,800
19,000
11,500
5,000
2,000
13,000
16,000
6,000
26, 000
30,000
1,400
2, 100
NM
NM
2,500
3,400
1,800
7, 000
9,500
4,800
2,900
2,200
                  46

-------
                          APPENDIX D

      SURVEY METER READINGS OF PARTICLES (continued)
Distance
(Miles)
9
9
9
9
9
9
9
9
9
34
34
39
39
39
39
44
44
44
44
Size
(H)
2
81
16
16
52
2
5
4
58
3
5
3
5
6
48
9
45
10
6
P + V
Activity*
(cpm)
28, 000
21,000
8,000
5,500
8, 500
6,000
1, 100
7,500
2, 100
650
650
2,500
1, 100
3,700
4,400
350
2,800
430
4,600
Distance
(Miles)
26
29
29
29
29
34
34
34
34
44
51
51
51
60
67
67
74
82

Size
(n)
6
6
13
50
21
17
8
10
18
10
8
18
21
15
51
21
4
5

P + Y
Activity*
(cpm)
1,200
7.500
1, 350
10,000
7,000
6,500
1,800
1,500
1, 100
170
8,000
7,500
350
2, 100
350
3,000
4,500
4,700

NM - Not Measured
*As measured by an RM-3A GM monitor.
**The particles from 6 and 7 miles were not located by surveying a
defined area.  They are not reported in Table 1 and Figure 1.
                               47

-------
                                              APPENDIX E
              PARTICLE SIZE, ACTIVITY AND DISTANCE CORRELATION COEFFICIENTS
Relationship
Linear
Exponential
oo Exponential
Power
Function
Activity (A)
Size (S)
A vs S
A vs log S
S vs log A
log S vs log A
Coefficient Size (S)**
(r) Distance (D)
(68 Data Points)
0.46 S vs D
0. 25* S vs log D
0. 34 log S vs D
0. 17* log S vs log D
Coefficient
(r)
(6 Data Points)
-0.44*
-0. 66*
-0.41*
-0. 64*
Activity
(A)**
Distance
(D)
A vs D
A vs log D
log A vs D
log A vs
log D
Coefficient
(6 Data Points)
-0.64*
-0. 69*
-0.65*
-0.71*
^Correlation coefficient not significantly different from zero at the 95% confidence level.
**Correlation performed on the average size or activity for a distance interval, rather than each particle.

-------
                           APPENDIX F



                    ISOTOPIC FRACTIONATION






Relative abundances of 235U fission products at one hour after fission



relative to "Mo, were obtained from Bolles  and Ballou.   The ratios of



fission  products identified for each sample were then related to the



amount  of 99Mo found.  These ratios, based on data from Table 4 in the



report are presented in Table F-l. Each ratio calculated for each



sample  was divided by the corresponding ratio calculated from Bolles



and Ballou to determine an "enrichment  factor" for the isotope relative



to the amount expected on the basis of 99Mo.   These enrichment factors



are presented in Table F-2.





From Table  F-2 it can be seen that the zirconiums,  103Ru, 140Ba, 141Ce,



and 147Nd are enriched relative to 99Mo,  while 132Te  and 143Ce are



depleted.   This might also be interpreted to  mean that 99Mo is depleted



relative to most of the other isotopes quantitated.   It is also observed



that the enrichment factors for 95Zr and  97Zr are generally the same



within each sample, although they may vary  between samples.  In



general, the enrichment factors for  the ceriums differ by about an



order of magnitude within each sample.  The activity values are



plotted  in Figures F-l and F-2 for the ceriums and zirconiums.



Linear  correlation coefficients were determined to be 0. 54 for the



141Ce/143Ce ratios and 0.97 for the 95Zr/97Zr ratios.  Similar cor-



relations may be determined for any other pair of isotopes.
                                49

-------
Table F-l.  Ratios * of fission product activities based on "Mo
Isotope
'5Zr
"Zr
"Mo
"»Ru
132Te
140 Ba
141Ce
UJCe
147 Nd
Bolles &
Ballou**
0.
4.
1.
0.
0.
0.
0.
1.
0.
046
05
00
041
58
23
093
92
12
20528
A B
ND
ND
1.00
ND
0.097
1.7
0.92
ND
ND
ND
ND
1. 00
ND
0.07
1.0
0.63
ND
ND
A
0.
21
1.

0.
0.
0.
0.
0.
21

00
ND
25
13
23
71
25
20540
B
0

1
0
0
0
12
0
1
.85
ND
.00
.31
.46
.87

.41
. 5
C
0.
16
1.

0.
0.
0.
0.
0.
21

00
ND
13
11
19
51
38
A
0.
55
1.

0.
1.
0.
2.
1.
20542
B
68

00
ND
68
3
88
0
0
0.
29-
1.
0.
0.
0.
0.
1.
0.
32
0
00
17
48
78
53
3
79
20543
0.
6.
1.
0.
0.

0.
0.

04
6
00
007
009
ND
001
009
ND
20544
0.
6.
1.

0.
0.
1.
0.
0.
1
2
00
ND
07
13
3
34
26
A
0.
74
1.
1.
0.
1.
1.
3.
1.
20545
B C
78

00
4
98
6
2
0
4
0.
84
1.
2.
0.
1.
1.
1.
0.
51

00
3
35
9
6
0
79
0.
5.
1.

0.
0.
0.
0.
0.
05
6
00
ND
02
23
08
23
09
D
0.
28
1.
0.
0.
0.
0.
1.
0.
31

00
75
21
82
71
2
77
20546
0.42
30
1.00
ND
0. 18
0.73
0. 11
1.2
0.70
''•'These ratios are based on calculated activities before being rounded off to two significant figures for Table  2.
**Values obtained from USNRDL-456.  Ratio of isotope activity to "Mo activity at H+l hour.
                                                                                50

-------
Table F-2.  Isotopic fractionation factor based on "Mo
Isotope
"Zr
"Zr
"Mo
103Ru
132Te
u°Ba
ulCe
U3Ce
U7Nd
20528
A
	
	
1
	
0. 17
7.6
9.9
...
	
B
...
...
1
...
0. 12
4. 5
6.8
---
	
A
4.6
5. 1
1
...
0.43
0.56
2. 5
0. 37
2. 1
20540
B
19
...
1
7.6
0.79
3.8
130
0. 21
13
C
4.6
3.9
1
...
0.22
0.48
2.0
0.26
3.2
20542
A
15
14
1
...
1. 2
5.6
9. 5
1.0
8.3
B
7
7.2
1
4. 1
0.83
3.4
5.7
0.68
6.6
20543
0.87
1.6
1
0. 17
0.015
...
0.01
0.005
	
20544
2. 2
1. 5
1
...
0. 12
0.56
14
0. 18
2.2
A
17
18
1
34
1.7
7.0
13
1.6
12
20545
B
11
21
1
56
0.60
8.3
17
0.54
6.6
C
1. 1
1.4
1
--.
0. 034
1.0
0.86
0. 12
0.75
D
6.7
6.9
1
18
0. 36
3.6
7.6
0.62
6.4
20546
9. 1
7.4
1
...
0. 31
3. 2
1.2
0.62
5.8
                                                                     51

-------
1O*
105
0)
U
r>
«
1O"
103
1

I I I I I I I
d
W
~ *®
W
I I II III
I I I I I I I I

« *
o
V
I I I I I I I I
I I
d
«-
^ 	
I I
03 10« 1Q5
141Ce
Figure F-l.     Ce versus    Ce activity for  selected Phoebus IB, EP-IV
             particles.

-------
F- i   i  i  l  I i
                              1	1—I   I  I  I  11
     1O6
     105
   N
   m
   o-
     104
     103
                      105
                                     1	1   I  I  I  I I  I	I    I    I   I   I  I I  I
                                           1O6
                                                                                107
                                              "Zr
Figure F-2.  95Zr versus 97Zr activity for selected Phoebus IB, EP-IV particles.



                                         53

-------
                             DISTRIBUTION

 1 -  15    SWRHL,  Las Vegas, Nevada
     16    Robert E. Miller,  Manager, AEC/NVOO, Las Vegas, Nevada
     17    Robert H. Thalgott, Test Manager, AEC/NVOO,  Las Vegas, Nev.
     18    Henry G. Vermillion, AEC/NVOO, Las Vegas, Nevada
     19    D. W. Hendricks,  AEC/NVOO, Las Vegas,  Nevada
     20    Robert R. Loux, AEC/NVOO,  Las Vegas, Nevada
     21    Central  Mail & Records, AEC/NVOO,  Las Vegas, Nevada
     22    D. Hamil, AEC/NVOO Library, Las Vegas, Nevada
     23    M. Klein, SNPO, Washington, D. C.
     24    R. Decker,  SNPO,  Washington, D. C.
     25    R. Hartfield, SNPO-C,  Cleveland, Ohio
     26    J. P. Jewett,  SNPO-N,  Jackass Flats, Nevada
27 -  30    R. Nelson, SNPO-N, NRDS, Jackass Flats,  Nevada
     31    William C. King, LRL,  Mercury,  Nevada
     32    Roger Batzel, LRL, Livermore,  California
     33    H. L. Reynolds, LRL,  Livermore, California
     34    H. T. Knight, LASL,  Jackass Flats, Nevada
     35    P. Gothels,  LASL, Los Alamos,  New Mexico
     36    Harry S. Jordan, LASL, Los Alamos,  New Mexico
     37    Charles I. Browne, LASL, Los Alamos,  New Mexico
     38    William E. Ogle, LASL, Los Alamos,  New Mexico
     39    F. L. Di Lorenzo, NTO, NRDS, Jackass Flats, Nevada
     40    H. G. Simens,  NTO, Aero-jet General Corp. , Jackass  Flats, Nev.
     41    R. A. Smith, NTO, NRDS, Jackass Flats, Nevada
     42    G. Grandy,  WANL, NRDS, Jackass Flats, Nevada
     43    E. Hemmerle,  WANL,  Pittsburgh, Pennsylvania

-------
    44    M.  I. Goldman, NUS, Washington,  D.  C.
    45    J. Mohrbacher, Pan American World Airways,  Jackass Flats,  Nev.
    46    P.  Allen, ARL/ESSA, AEC/NVOO, Las  Vegas, Nevada
    47    Martin B.  Biles, DOS, USAEC, Washington, D. C.
    48    H.  Booth,  ARL/ESSA,  AEC/NVOO, Las Vegas, Nevada
    49    C.  Anderson, EG&G,  Las Vegas, Nevada
    50    R.  S. Davidson, Battelle Memorial Institute, Columbus,  Ohio
    51    Byron Murphey, Sandia Corp. , Albuquerque, New Mexico
    52    Maj. Gen. Edward B. Ciller, DMAS USAEC,  Washington, D.  C.
    53    Chief, NOB, DASA, AEC/NVOO, Las V^egas, Nevada
54 - 55    Charles  L.  Weaver,  PHS, BRH, Rockville, Maryland
    56    John C.  Villforth, Director, BRH,  Rockville, Maryland
    57    Arden Bicker,  REECo Rad. Safe. , Mercury, Nevada
    58    Southeastern Radiological Health Lab. ,  Montgomery, Alabama
    59    Northeastern Radiological Health Lab. , Winchester, Mass.
60 - 61    DTIES Oak Ridge, Tennessee
    62    Wm.  Link,  BRH Library, Rockville, Maryland
    63    John Bailey, Office  of Information,  BRH, Rockville, Maryland
64 - 65    Joseph Maher, International Atomic Energy Ass'n, Vienna, Austria

-------