United States       Office of Radiation Programs  ORP/LV-80-1
            Environmental Protection   Las Vegas Facility      January 1980
            Agency         P.O. Box 18416
                        Las Vegas NV89114
            Radiation


&EPA      Particle Size Distribution


            of Yellowcake  Emissions


            at the United Nuclear-


            Churchrock Uranium Mill

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PARTICLE SIZE DISTRIBUTION OF YELLOWCAKE EMISSIONS
  AT THE UNITED NUCLEAR-CHURCHROCK URANIUM MILL
                  C. W. Fort Jr.
                    R. Douglas
                    R. Gauntt*
                 A. R. McFarland*
                   Consultants
                  January  1980
  United States Environmental Protection Agency
Office of Radiation Programs - Las Vegas Facility
             Las Vegas, Nevada  89114

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                                  DISCLAIMER

     This  report  has  been  reviewed  by  the  Office of  Radiation  Programs  -
Las  Vegas  Facility,  U.S.  Environmental  Protection Agency,  and  approved  for
publication.    Mention  of  trade  names  or  commercial  products  does  not
constitute endorsement or recommendation  for their use.

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                                   PREFACE

    This study was  conducted by the Office of  Radiation  Programs  - Las Vegas
Facility (ORP-LVF)  of  the U.S.  Environmental  Protection Agency.   The purpose
of  the  study  was  to  evaluate  the  particle  size distribution  of yellowcake
(uranium concentrate)  emissions from  the yellowcake  processing  stacks at  a
uranium  mill.    This  is  one of a  series of similar  studies  that  are being
conducted at several uranium mills.

    As  a  follow-on study  to yellowcake  emission  rate tests  at  six  uranium
mills, this work supports the requirements of Section 122 of the Clean Air Act
Amendments of 1977, Public Law  95-95.   Section  122 directed  EPA to review all
relevant  information  and  determine if emissions of  radionuclides  cause  or
contribute  to  air  pollution.    The  uranium  milling  industry   is  one  of  the
source  categories  being  considered  by  the  Office  of Radiation  Programs  in
implementing the Clean Air Act.

    The field  work  for this study was  conducted  by  Mr.  Charles W.  Fort  with
the assistance of  Mr.  Richard Douglas.   The samples  were analyzed by Dr.  Emil
Kalil  at  Uranium-West  Laboratories.     Following  initial  analysis  of  the
resulting data by  Mr-  Fort, Dr. Andrew McFarland, consultant  to ORP-LVF,  and
Mr.  Randy  Gauntt  performed  the final   data  analysis and  report  preparation.
Dr. McFarland  is a  Professor of Civil  Engineering at Texas A&M University and
Mr. Gauntt is a research associate at Texas A&M.

    We would appreciate receiving any comments on this report that  readers may
have to offer.
                                  Donald W. Hendricks
                                  Director, Office of
                                  Radiation Programs, LVF

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                                   ABSTRACT

     Tests  were conducted  to  characterize the  particle size  distribution  of
yellowcake dust from the packaging and dryer  stacks  of a uranium  mill  in New
Mexico.   A multistage  inertia!  impactor was  used to  sample  the  particulate
matter  to  provide a  basis for  determining   particle  size  distributions  and
emission rates.   The  principal  results, from  four  tests with  the  packaging
stack and eight tests with  the dryer  stack, are as follows:

      Parameter               Packaging Stack              Dryer Stack
Mass median aerodynamic
  particle diameter               1.62 ym                    1.19 ym
Respirable fraction
(Utot activity associated
with sizes 1 2.5 ym)                69%                        90%
Concentration of            558 ± 192 pCi/dscm         6120  ±  1070  pCi/dscm
Utot (equivalent         (0.971 ± 0.335 mg/dscm)       (10.7  ±  1.86  mg/dscm)
      in stack
Total emission rate         1.19 ± 0.397 yCi/hr         62.5 ± 15.8 yCi/hr
of Utot (equivalent        (2.07 ± 0.692 g/hr)           (109 ± 27.1 g/hr)

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                                   CONTENTS

                                                                          Page
PREFACE                                                                    iii

ABSTRACT                                                                    iv

LIST OF FIGURES                                                             vi

LIST OF TABLES                                                              vi

LIST OF ABBREVIATIONS AND SYMBOLS                                          vi i

ACKNOWLEDGMENTS                                                           viii

INTRODUCTION                                                                 1

SAMPLING METHODOLOGY                                                         3

ANALYSIS AND RESULTS                                                         5

SUMMARY AND CONCLUSIONS                                                     13

REFERENCES                                                                  15

APPENDICES

    A -- Basic Impactor Data                                               A-l

    B -- Summary of Size Parameters and Total Mass for
           Individual Tests                                                B-l

    C -- Composite Size Distribution Data                                  C-l

    D -- Example of Calculations for Determination of
           Particle Concentration and Emission Rate                        D-l

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                               LIST OF FIGURES

Number                                                                   Page

   1.  Cumulative Size Distribution of Yellowcake Particles
       in Packaging Stack                                                  6

   2.  Cumulative Size Distribution of Yellowcake Particles
       in Dryer Stack                                                      7

   3.  Mass Frequency of Particulate Matter from Packaging Stack          11

   4.  Mass Frequency of Particulate Matter from Dryer Stack              12
                                LIST OF TABLES

Number                                                                   Page

   1.  Test Parameters and Information                                     8

   2.  Emission Characteristics of Packaging and Dryer Stacks              9

   3.  Summary of Emission Characteristics for Individual  Tests           14

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                      LIST OF ABBREVIATIONS AMD SYMBOLS

    A combination of both  English  units  and  the International  System of Units
(SI) are used in this  report.   For the most  part the units dealing  with  mass
and  particle  size  follow SI;  however,  since  gas flow  rates are  typically
measured in the  English  system, certain flow parameters are expressed  corre-
spondingly.  In addition, gas volumes can be presented either  dry  or moist.   A
summary  of  the  special  gas  volume,  flow  rate, and  radioactivity  units  and
abbreviations used herein follows:

    acf = actual  cubic feet.   The units of gas volume that  include the
          moisture component  and that correspond to the actual  pressure
          and temperature of the gas.

   dscf = dry standard cubic feet.   Gas volume, with moisture  fraction
          removed, that would exist if the temperature were 68°F and
          the pressure were 29.92 in. Hg.

   acfm = actual  cubic feet per minute.  Units of volumetric flow  rate
          of gas based on actual conditions.

  dscfm = dry standard cubic feet per minute.  Flow rate of gas that
          would exist if moisture were deleted and if temperature  and
          pressure were as given above for units of dscf.

   dscm = dry standard cubic  meters.  Identical  to dscf except  converted
          to SI.   1 dscm = 35.3 dscf.

   utot = total  uranium activity, i.e., the sum of U-238,  U-234, and
          U-235 activities.

   pCi  = picocurie = 10~12 curie.

    ym = micrometer = 10-6 meter.

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                               ACKNOWLEDGMENTS

      The authors  wish  to express  their appreciation to  Dr.  Noel  Savignac,
United Nuclear Corporation -  Albuquerque, and  Mr-  Todd  Miller and  his  staff  at
the United Nuclear Churchrock  uranium  mill  in Churchrock, New Mexico  for the
assistance and cooperation they extended  during this  study.
                                    vm

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                                 INTRODUCTION

    From May 16 to May 21, 1979, a series of tests were conducted to determine
the size distributions of the yellowcake*  particles  vented  from  the dryer and
packaging  stacks  at  the   United   Nuclear  Corporation   uranium  mill   near
Churchrock, New Mexico.   The  exhaust gases from both the  packaging and  dryer
operations  are passed through  air  pollution  control  equipment  before  being
discharged through the stacks.    A  Joy  venturi  wet scrubber  is used on  the
packaging gases and a Sly "Impi-Jet" scrubber is used for the dryer stack.

    The  basic  sampling tool used  in these tests was  an  eight-stage inertial
impactor fitted with  an  after-filter (Andersen, 1977).   This  device collects
particles  in  a manner compatible with  determining  the mass distributions  of
particles as a function of aerodynamic diameter (Da)-**

    EPA is considering the adoption of size standards for airborne particulate
matter  (Miller et al., 1979).   Recommended is a standard  based on inhalable
particulate  matter  defined  as  _<15  ym  with  emphasis  also on   the <2.5  ym
fraction.  Particles  in this  latter  size range are  capable of  penetrating the
gas-exchange region of the  lower respiratory tract and will  be  referred  to  in
this report as respirable particulate matter.
*  Yellowcake  is  the  generic  name  given  the  packaged  uranium  concentrate
produced by  uranium mills.   It  is generally a dry, powdery  material  having  a
variety  of  chemical  forms  ranging  in  color from  bright yellow  through olive
green  to black, depending  on each mill's  process.    The  uranium content  of
yellowcake  is  typically  expressed  as  an  equivalent  mass  of  one   of  these
compounds,  UsOg,  as  in  this report.    However,  since the  chemical   form  of
the United  Nuclear  yellowcake  is  unknown,  it is  important  for  the  reader  to
realize  this material  may  not  be  UsOg or  have the solubility  character-
istics of 0303.
** Aerodynamic diameter relates the aerodynamic behavior of irregularly shaped
particles with varying densities  to  the diameter  of  a  unit  density  spherical
particle  that  would   behave identically  under  the   same   conditions.    All
particle size references in this report are to aerodynamic  diameters.

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    Data from an inertia! impactor can be used to  characterize  the  respirable
fraction.    However,  the  inertia!  impactor  used  in  these studies  does  not
does  not  provide  size  resolution  for  particles   larger  than  approximately
10  yin.    Highly  definitive  information,  therefore.,  is  not  obtainable  on
material in the inhalable/non-inhalable  fractions.

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                             SAMPLING METHODOLOGY

    Four  sampling  locations  at  90°  intervals  (one  in  each  of  the  four
quadrants) were used  for  the dryer stack.   Prior  to  each  test, the  velocity
distribution  for  the quadrant  of  interest was  determined  with a pi tot  tube
(USEPA, 1977).  A sampling point was selected corresponding  to  the  location  at
which  the  dynamic  pressure  was  equal  to  the  average  pressure  for  that
quadrant.    By coincidence, each of  the four sampling  points  was  3.4  inches
from  the  stack wall.   Duplicate  tests were  conducted at  each  of   the  four
points.  The inside diameter of the stack is 33.5 inches.

    The  packaging  stack,  which   is  11.25  inches  in  diameter,,  would  not
accommodate the  entire impactor without  causing undue flow blockage;  there-
fore, the  criterion for location of a sampling point was that  the  impactor  be
inserted  into  the stack  to  a  depth whereby the  flow  blockage would be  less
than  2  percent.   Two locations were used  with the points  90°  apart   and  3.75
inches  from the  wall.    Duplicate  tests  were  conducted  at each  of the two
points.

    In preparation for  a  test, glass  fiber collection substrates and a glass
fiber  after-filter were  placed in the  impactor, and  the  impactor   was  then
inserted  into  the  stack.   The  unit was  equipped with  heater tapes to  enable
the impactor  to  operate  well  above  the stack dew-point temperature.   Before
sampling  began,   the   impactor was  allowed  to   equilibrate  with the  stack
temperature for 30 minutes.  The sampling  flow was then started,  and  sampling
continued  for a period of 30 to 75  minutes.

    At the  completion  of  particle  collection,   the  impaction  substrates and
after-filter were  removed and  sent  to Uranium-West Laboratories  (15515  Sunset
Blvd., Suite  B07,  Pacific Palisades,  California    90272) for determination  of
the total' uranium deposited on each  element.    Samples  were  analyzed by  a
delayed-neutron counting  technique.   This  method has a detection  sensitivity
of 0.17 pCi Utot (0.25 ygm Utot).

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    A program was developed for the Hewlett Packard 97 calculator (Fort, 1979)
to compute impactor stage cut-points.   The program incorporates  the effects of
such sampling variables as flow rate,  temperature  and  pressure  as well  as the
most current  impactor calibration  data  published by  Gushing  et  al.  (1976).
The program has  been  validated through  an  independent  cross-check (McFarland,
1979).

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                             ANALYSIS AND RESULTS

    The basic  test  parameters and variables  are summarized in Table 1.   For
each test, the  sampler  was  operated  for a  period  of  30-75 minutes at a  flow
rate of approximately 0.5  acfm.   Total  flow  rate  through  the  packaging  stack
ranged from 1217 to 1275 dscfm and through  the  dryer  stack from 4930 to  7130
dscfm.

    The particle size data  from  use  of the  inertial  impactor  are tabulated in
Appendix A, where the quantity  of uranium  associated  with  each stage of  the
impactor is  given  as  a function  of  the cut-point particle size of the  stage
(aerodynamic particle diameter for which the particular impactor  stage has  a
50  percent  collection  efficiency).    For example,  in  Test A of  the  packaging
stack, 90.4 yg  of uranium was collected on  the  stage  that has a  cut-point  of
11.0  ym.   Similarly,  1.7 yg  was collected on  the stage with a  cut-point  of
10.2  ym.   Thus, of  the material   collected  during  Test A,  90.4 yg of uranium
had aerodynamic sizes O.1.0 ym,  and  1.7 yg  had  aerodynamic sizes between  10.2
and 11.0 ym.

    Normalized  cumulative size  distributions were  calculated  for each test.
The results for the packaging stack  are plotted in Figure 1 and those for the
dryer  stack  in Figure  2.   Smooth composite curves  fitted  through  the  data
points  can be  used  as a  basis  for estimating the  mass median  aerodynamic
particle  size   (corresponding  to the  50th  percentile)  and the  fraction  of
material in the respirable range.  These values  (Table 2) show the mass  median
sizes to be 1.62 and 1.19 ym for the  packaging and dryer stacks, respectively.
The corresponding values for the respirable fractions  are 69 and 90 percent.

      Cumulative distributions for the individual tests were also plotted, and
determinations  were  made  of  the  mass  median  sizes  and  the  respirable
fractions.  A summary of these data appears in Appendix B.

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   AERODYNAMIC  ARTICLE  DIAMETER,  DQ ,
FIGURE 1.   CUMULATIVE SIZE DISTRIBUTION OF YELLOWCAKE PARTICLES
                   IN PACKAGING STACK

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                                            TABLE  1.   TEST PARAMETERS AND INFORMATION
CO
Stack
Packaging



Dryer







Test
A
B
C
D
E
F
G
H
I
J
K
L
Sampling
Point
1
1
2
2
1
1
2
2
3
3
4
4
Test
Time
Minutes
45
60
60
75
60
75
30
30
45
30
30
30
Temperature
(degrees F)
91
77
77
84
132
166
152
139
146
154
139
140
Fl ow Rate
(acfm)
0.507
0.520
0.532
0.539
0.419
0.419
0.594
0.601
0.502
0.495
0.536
0.498
• Stack Moisture
Mol Fraction
0.029
0.026
0.025
0.027
0.060
0.060
0.060
0.058
0.060
0.058
0.051
0.070
Stack Flow
Rate (dscfh)
1217
1260
1265
1275
4970
4930
7020
7130
5830
5700
6320
5830

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         TABLE 2.  EMISSION CHARACTERISTICS OF PACKAGING AND DRYER STACKS
Parameter
                               Packaging Stack
                                       Dryer  Stack
Mass Median Aerodynamic
  Diameter
                                1.62 urn
                                        1.19  ym
Average Respirable
  Fraction
                                 0.688
                                         0.902
Geometric Mass Mean
  Aerodynamic Diameter
                                  2.19 ym
                                          1.28  ym
Geometric Standard
  Deviation
                                 2.95
                                         1.92
Total Concentration
  of Utot,
  (U308)*
                           558 ± 192   pCi/dscm
                        (0.971 ± 0.335 mg/dscm)
                                   6120 ± 1070 pCi/dscm
                                  (10.7 ± 1.86 mg/dscm)
Respirable Concentration
  of
  (U308)

Average Emission Rate
  of Utot>
  CU308)
   382 ± 123 pCi/dscm
(0.665 ± 0.215  mg/dscm)


  1.19 ± 0.397  yCi/hr
 (2.07 ± 0.692  g/hr)
                                                           5750 ± 760 pCi/dscm
                                                         (10.01 ± 1.32 mg/dscm)
                                                           62.5 ± 15.8 yCi/hr
                                                           (109 ± 27.1 g/hr)
Average Respirable Emission
  Rate of Utot>          °-812 ± °-253
                         (1.41 ± 0.441 g/hr)
                                                           56.3 ±  14.2  yCi/hr
                                                          (98.1 ±  24.7  g/hr)
'Quantities in parentheses represent Utot expressed as equivalent
** Error terms are one standard deviation of replicate tests.

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    I he composite curves. Figures 1 and  2,  were  each divided into size inter-
vals of  approximately equal  logarithmic increments,  Aln(D), and  derivative
approximations  at  the  interval  midpoints  (geometric means)  were  formed  as
AG(D)/Aln(D), where AG(D) represents the difference  of the  cumulative distri-
bution values at the  interval  upper and lower particle  size boundaries.   The
results of this  procedure  appear in Appendix C  and  are  plotted in  Figures  3
and  4  as   AG(Da)/AlN(Da)  versus  aerodynamic   diameter,   Da.     Since   the
irnpactor does not  provide  information on the  distribution  of  particles  with
sizes  greater than  approximately 10  ym,  an upper boundary  size was  assumed
for the  largest  fraction.   The values selected  were  20  ym  for the  packaging
stack  and  13 urn for  the  dryer stack  data.   The bimodal appearance of these
mass densities may be due,  in part,  to the selection  of the upper  limit of the
largest size  interval;  however,  the plot of the  packaging  stack  data, Figure
3,  illustrates  that  considerable material   is associated with particle  sizes
_<10ym.  Figure  1 shows that  approximately 20  percent of  the uranium mass  from
the packaging stack  is  associated  with  these larger  sizes.   Correspondingly,
only 5  percent  of  the uranium mass collected from the dryer stack  is seen  to
be associated with particles larger  than 10  ym.

    The  geometric  mass  mean  aerodynamic  diameter,  Dg,  and  the  geometric
standard  deviation,   sg,  for  the  distributions  in  Figures 3  and  4  were
computed using:

         In Dg = z (In Di}  mp)  * AGj

         where D-j jfnp = midpoint size of  ith  interval
               Di,mp = (Di,u * DijL)1/2
               DI,U = interval  upper boundary
               ^i,L = interval  lower boundary
and:
         In2  sg =  i  (In  Di5mp -  In  Dg)2  *  AGi          (McFarland,1978)

in conjunction with the data tabulations of  Appendix  C.   The results are given
in Table 2,
                                     10

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      AERODYNAMIC  PARTICLE  DIAMETER,  D  ,
FIGURE 3.  MASS FREQUENCY OF PARTICIPATE MATTER FROM PACKAGING STACK

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     AERODYNAMIC  PARTICLE  DIAMETER,  DQ ,
FIGURE 4.  MASS FREQUENCY OF PARTICULATE MATTER FROM DRYER STACK

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    Using  the  procedure  outlined  in Appendix  D,  total  concentrations  and
respirable concentrations were  computed  for each  test.    Concentrations  were
calculated  in  terms  of  pCi  Utot/dscm  and mg  UsOg/dscm.     Total  and  re-
spirable  emission  rates  (pCi  Utot/nr  and  g  UsOs/hr)  were  then  calculated
for each test using the dry standard concentrations and the dry standard stack
flow rates.   The basic assumptions  used  in calculating emission rates  from
impactor data are (1)  a homogeneous yellowcake  concentration  exists throughout
the stack,  and  (2) the  gas velocity at  the  sampling  point  is  the  average
velocity for the stack.  These results are summarized by test  in Table 3.   The
values of the parameters for each stack in Table 3 were averaged,  and  a  stand-
ard deviation was calculated.  These values are listed in Table 2.
                           SUMMARY AND CONCLUSIONS

     The yellowcake  particle  emissions  from  the  uranium  mill  packaging  and
dryer stacks can be characterized by mass median aerodynamic diameters  of 1.62
and  1.19  ym, respectively.   If  respirable  particulate matter is  defined  as
particles  with  aerodynamic sizes <2.5  ym,  then  the  packaging  stack  has  a
respirable  fraction  of  69 percent  while  that  of the dryer  is  90  percent.
Since both stacks are controlled with scrubbers, the actual  size distributions
and respirable fractions are quite dependent upon the scrubber performance.

    Approximately 20 percent of  the  particulate  mass  emitted  by the packaging
stack was  associated with aerodynamic  particle  sizes larger than  10  ym.    A
scrubber should  efficiently  remove these larger  particles  from the distribu-
tion, so it  appears  that  the  packaging stack scrubber may  have abnormal  mist
carryover or may have other operational or design problems.

    The  packaging  stack  discharges  an  average  of 1.19  yCi  Ut0t/hr  (2.07  g
UsOs/hr)  to the  atmosphere.     The  rate  for the dryer  stack  is 62.5  yCi
Utot/hr (109 g U308/hr).
                                      13

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TABLE 3.  SUMMARY OF EMISSION CHARACTERISTICS FOR INDIVIDUAL TESTS
Stack
Packaging



Dryer







Test
Number
A
B
C
D
E
F
G
H
I
J
K
L
Total Uranium
Concentration
626.23
767.44
527.51
310.53
4760.76
6266.36
6706.62
6272.10
6351.88
7475.20
6813.95
4287.78
Respirable Uranium
Concentration
(pci Ut0t/dscm)
456.90
491.34
363.92
214.68
4047.85
5827.25
6035.61
5707.86
5778.46
6727.85
6063.74
5772.14
Total Uranium
Emission Rate
(yCi Utc,t/hr)
1.296
1.636
1.138
0.679
40.161
52.521
79.958
76.026
62.949
72.391
73.128
42.495
Respirable Uranium
Emission Rate
(yCi Utot/nr)
0.946
1.047
0.785
0.468
34.137
48.739
71.962
68.804
57.283
65.152
65.230
39.095













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                                  REFERENCES

Andersen 2000, Inc.  (August  1977).   Operating  Manual  for Andersen 2000, Inc.:
Mark II and Mark III Particle Sizing Stack Samplers.   Atlanta, Georgia.

Gushing, K.  M.,  G.  E.  Lacey,  0.  D.  McCain  and W.  B.  Smith  (October 1976).
Particulate Sizing Techniques for Control Device Evaluation:  Cascade
Impactor Calibrations.  Ind. Env.  Res. Lab., U.S. EPA, Research Triangle
Park, N.C.  and Southern Research Inst., Birmingham, Alabama.  Contract No.
EPA-68-02-0273.  EPA 600/2-76-280.

Fort, C. W. (1979).  "Impaction Stage Cut-point Calculations for the
Anderson Mark  III  Impactor."  An original program for  the Hewlett Packard 97
calculator (unpublished).

McFarland,   A.  R.   (March  1978).    Aerodynamic  Particle  Sizing  Air  Quality
Laboratory Publication, Texas ASM University.

McFarland,  A. R. (1979).  Personal  Communication.

Miller, F.  J., D.  E. Gardner,  J.  A.  Graham,  R. E.  Lee,  Jr., W. E. Wilson,  and
0. D. Bachmann  (1979).   "Size Considerations  for Establishing  a  Standard  for
Inhalable  Particles,"   Journal  of  the Air  Pollution  Control  Association,
29, 6, (June 1979), pp 610-615.

U.S.  EPA,  (August  18,  1977).   Standards  of  Performance for  New Stationary
Sources:  Method 1 Sample and Velocity Traverses for Stationary Sources.
Federal Register, 42, 160.
                                      15

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APPENDIX A
Stack
Packaging








Packaging







Packaging







Packaging







Basic Impactor Data
Sampling Impactor Aerodynamic
Test Point Cut-Point Size, um
A 1 11.0
10.2
6.4
4.3
2.3
1.1
0.65
0.36
0 (Filter)
B 1 10.8
10.0
6.2
4.2
2.3
1.1
0.64
0.35
0
C 2 10.6
9.9
6.2
4.2
2.2
1.0
0.63
0.35
0
D 2 10.6
9.9
6.2
4.2
2.2
1.0
0.63
0.35
0
Uranium
Collected,yg
90.4
1.7
9.0
13.0
48.5
285.4
80.2
24.8
5.8
166.8
10.4
37.8
37.1
118.2
358.3
151.8
58.8
24.6
137.1
3.2
11.9
12.6
70.3
265.7
112.3
41.3
23.2
84.5
4.1
16.2
15.4
52.2
179.6
77.6
37.4
31.0
        A-l

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                        APPENDIX  A  (continued)




                          Basic  Impactor  Data
Stack
Dryer








Dryer








Dryer








Dryer







Sampling Impactor Aerodynamic
Test Point Cut-Point Size, um
E 1 12.5
11.6
7.2
4.9
2.6
1.2
0.74
0.41
0
F 1 12.7
11.8
7.4
5.0
2.7
1.2
0.75
0.42
0
G 2 10.6
9.8
6.1
4.1
2.2
1.0
0.61
0.33
0
H 2 10.4
9.7
6.0
4.1
2.2
1.0
0.60
0.33
Uranium
Collected.ua
0*
186.8
16.0
55.2
336.7
1442.4
1014.5
872.0
295.5
87.4
16.1
24.7
35.0
182.9
2544.4
2277.7
1160.1
268.8
89.6
23.4
31.8
52.0
316.9
2338.4
966.0
227.1
28.9
34.3
11.8
22.4
40.4
338.2
2343.6
936.6
182.3
                                           0                         26.7
*Uranium on first impactor stage combined  with  second  stage.



                                     A-2

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APPENDIX A (continued)
  Basic Impactor Data
Stack
Dryer








Dryer








Dryer








Dryer








Sampling Impactor Aerodynamic
Test Point Cut-Point Size,- um
I 3 11.5
10.6
6.6
4.5
2.4
1.1
0.67
0.37
0
J 3 11.6
10.8
6.7
4.5
2.4
1.1
0.68
0.37
0
K 4 11.1
10.2
6.4
4.3
2.3
1.1
0.64
0.35
0
L 4 11.5
10.6
6.6
4.5
2.4
1 .1
0.67
0.37
0
Uranium
Collected, UQ
163.9
17.1
22.8
30.8
222.5
2401 .1
1450.0
546.5
74.5
163.5
14.8
21.7
30.8
187.1
1771.3
1163.5
373.7
45.3
164.1
17.5
28.0
45.5
238. 2
2050.1
1022.6
252.7
29.5
63.6
10.0
11.9
18.1
85.8
926.8
842.5
213.5
28.9
             A-3

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APPENDIX B

Stack Test
Packaging A
B
C
D
Dryer E
F
G
H
I
J
K
L
Summary of Size Parameters
Total Mass for Individual
Mass Median
Aerodynamic Diameter,
1.55
1.77
1.56
1.52
1.17
1.11
1.25
1.27
1.21
1.18
1.35
1.18
and
Tests
Respirable
urn Fraction, %
73.0
64.0
69.0
69.0
85.0
92.8
90.0
90.5
91.0
90.0
89.2
92.0

Total Uranium
Collected, mg
0.5588
0.9638
0.6776
0.4980
4.2191
6.5471
4.0741
3.9363
4.9372
3.7717
3.8484
2.2011
       B-l

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APPENDIX C
Composite
C.I Packaging Stack
Interval
Lower
Size
DL
0.25

0.32

0.40

0.50

0.64

0.80

1.0

1.28

1.60

2.0

2.5

3.2

4.0

5.0

6.3

8.0

10.0

20.0
In DL
-1.3863

-1.1394

- .9163

- .6931

- .4463

- .2231

0

0.2469

0.470

0.6931

0.9163

1.1632

1.3863

1.6094

1.8405

2.0794

2.3026

2.9957
G(DL)
0.008

0.010

0.025

0.059

0.100

0.158

0.235

0.353

0.492

0.600

0.685

0.730

0.750

0.768

0.780

0.795

0.810

1.000
Size Distribution Data
Aln(D)

0.2469

0.2231

0.2231

0.2469

0.2231

0.2231

0.2469

0.2231

0.2231

0.2231

0.2469

0.2231

0.2231

0.2311

0.2389

0.2231

0.6931

A6(D)

0.002

0.015

0.034

0.041

0.058

0.077

0.118

0.139

0.108

0.085

0.045

0.020

0.018

0.012

0.015

0.015

0.190

AG(D)
Aln(D)

0.00810

0.06722

0.1524

0.1661

0.2599

0.3451

0.4780

0.6229

0.4840

0.3809

0.1823

0.0896

0.0807

0.0519

0.0628

0.0672

0.2741

Interval
Midpoint
D
mp, \im

0.280

0.358

0.447

0.566

0.716

0.894

1.131

1.431

1.789

2.236

2.828

3.578

4.472

5.612

7.099

8.944

14.142

        C-l

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APPENDIX C
Composite
:.2 Dryer Stack
Interval
Lower
Size
DL
0.25

0.32

0.40

0.50

0.64

0.80

1.0

1.28

1.60

2.0

2.5

3.2

4.0

5.0

6.3

8.3

10.0

13.0
In DL
-1.3863

-1.1394

- .9163

- .6931

- .4463

- .2231

0

0.2469

0.470

0.6931

0.9163

1-1632

1.3863

1.6094

1.8405

2.1163

2.3026

2.5649
G(DL)
0

0

0.01

0.03

0.10

0.20

0-35

0.55

0.725

0.850

0.91

0.95

0.95

0.952

0.955

0.956

0.958

1.0
Size Distribution Data
Aln(D)

0.2469

0.2231

0.2231

0.2469

0.2231

0.2231

0.2469

0.2231

0.2231

0.2231

0.2469

0.2231

0.2231

0.2311

0.2757

0.1863

0.2624

AG(D)

0

0.01

0.02

0.07

0.10

0.15

0.20

0.175

0.125

0.060

0.040

0

0.002

0.003

0.001

0.002

0.042

AG(D)
Aln(D)

0

0 . 0448

0.0896

0.2836

0.4481

Q.6722

0.8102

0 . 7842

0.5602

0.2689

0.1620

0

0.0089

0.0130

0.0036

0.0107

0.1601

Interval
Midpoint
D
mpj ym

0.280

0.358

0.447

0.566

0.716

0.894

1.131

1.431

1.789

2.236

2.828

3.578

4.472

5.612

7.099

9.110

11.402

        02

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                            APPENDIX D

           Example of Calculations for Determination of
             Particle Concentration and Emission Rate
1.  Select Packaging Stack Test A for sample calculation.
2.  From Table I and Appendix B:
      Stack flow rate =1217 dscfm
      Moisture = 0.029 (mol  fraction)
      Temperature = 91 F
      Total mass of UL Oft collected = 0.6589 mg
                     O O
      Respirable fraction = 73%
      Sampling rate = 0.507 acfm
      Test time = 45 min

3.  Calculate the volume of air sampled based on dry conditions,

              
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                            APPENDIX D (continued)
4.  Conversion of Utot to equivalent
      6.77 x 105 pCi Ut0t/gm Utot * 0-848 gm Utot/9"1
                               = 5.74 x 105 pCi Utot/gm
5.  Total concentration of Utot °r ^303 in stack:
      Total concentration Utot = 378 pCi Utot * 0.6034 dscm
                               = 627 pCi Utot/dscm
      Total concentration UaOg = 627 pCi Utot/dscm * 5-74 x lo5 Pci
                                 Utot/9 U308
                               = 1.092 mg/dscm

6.  Respirable concentration of Utot:
      Respirable concentration = 627 pCi Utot/dscm * 0.73
                               = 458 pci Utot/dscm

7.  Total emission rate of Utot:
      Total emission rate = 627 pCi Utot/dscm * 1217 dscfm *
                            1 m3/3531 ft3
                          = 2.16 x 104 pci Utot/min
                          = 1.30 x 106 pci/min * yCi/106 pCi
                          =1.30 yCi Utot/hr
8.  Emission rate of respirable Utot:
      Respirable emission rate = 0.73 * 1.30 yCi Utot/nr
                               = 0.95 yCi Utot/hr
                                       D-2

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                                    TECHNICAL REPORT DATA
                             (Please read Instructions on the reverse before completing)
 1. REPORT NO.
                               2.
                                                             3. RECIPIENT'S ACCESSION NO.
 4. TITLE AND SUBTITLE
  Particle Size  Distribution of Yellowcake Emissions
  at the United  Nuclear-Churchrock Uranium Mill
                                  5. REPORT DATE
                                      January 1980
                                  6. PERFORMING ORGANIZATION CODE
 7. AUTHOR(S)
  C.W. Fort, Jr.,  R.  Douglas, R. Gauntt,  and
  A.R. McFarland
                                                             8. PERFORMING ORGANIZATION REPORT NO
9. PERFORMING ORGANIZATION NAME AND ADDRESS
  Office of Radiation Programs-Las  Vegas  Facility
  U.S. Environmental  Protection Agency
  P.O. Box 18416
  Las Vegas,  Nevada  89114
                                                             10. PROGRAM ELEMENT NO.
                                  11. CONTRACT/GRANT NO.
 12. SPONSORING AGENCY NAME AND ADDRESS
                                                             13. TYPE OF REPORT AND PERIOD COVERED
                                                             14. SPONSORING AGENCY CODE
 15. SUPPLEMENTARY NOTES
 16. ABSTRACT
    Tests were conducted to characterize  the particle size distribution of yellowcake dust
 Tom the packaging and dryer  stacks of a uranium mill  in New  Mexico.   A  multistage iner-
 ;ial impactor was  used to sample the particulate matter to provide  a  basis for determining
 ^article size  distributions  and emission rates.  The  principal  results,  from  four tests
 \nth the packaging stack and eight  tests  with the dryer stack,  are  as  follows:
      Parameter                Packaging Stack             Dryer Stack
 lass median aerodynamic
  particle diameter               1.62 ym                   1.19 ym
 lespirable function
 'utot activity associated
 vith size _< 2.5 ym)

 oncentration of
 ^    (equivalent
      in stack
 otal  emission rate
 f utot (equivalent
         69%

  558 ± 192 pCi/dscm
(0.97 ± 0.335 mg/dscm)
  1.19 ± 0.397 yCi/hr
 (2.07 ± 0.692 g/hr)
        90%

 6120 ± 1070 pCi/dscm
(10.7 ± 1.86 mg/dscm)
  62.5 ± 15.8 yCi/hr
  (109 ± 27.1 g/hr)
                                 KEY WORDS AND DOCUMENT ANALYSIS
                  DESCRIPTORS
                    b.IDENTIFIERS/OPEN ENDED TERMS  C. COSATI Field/Group
  Particle Size  Distribution
  Uranium Isotopes
                                                     1407
                                                     1802
                                                     Yellowcake
 !. DISTRIBUTION STATEMENT

  Release to public
                    19. SECURITY CLASS (This Report)
                      Unclassified
                                                                           21. NO. OF PAGES
                                               20. SECURITY CLASS (This page)
                                                 Unclassified
                                                                           22. PRICE
EPA Form 2220-1 (Rev. 4-77)   PREVIOUS EDITION is OBSOLETE

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