MIDWEST RESEARCH INSTITUTE
                                                   REPORT
     COLLECTION, ANALYSIS AND CHARACTERIZATION OF VERMICULITE  SAMPLES
              FOR FIBER CONTENT AND ASBESTOS CONTAMINATION
                               TASK 32
                             FINAL REPORT

                          September 27,  1932

                    EPA Prime Contract No. 68-01-5915
                       MRI Project No. 4901-A32
                             Prepared for

                  U.S. Environmental Protection Agency
                Office of Pesticides and Toxic Substances
                         Field  Studies Branch
                          401 M Street, S.W.
                        Washington, D C. 20A60

               Attn:  Dr. Frederick Kutz, Project Officer
                     Mr. Thomas Dixon, Task Manager
MIDWEST RESEARCH INSTITUTE  -'.?rj VOI.KE n lOULCVAHD. KANSAS CiTY. MISSOURI 641 "0  •  BIG 753-7600

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        COLLECTION,  ANALYSIS AND CHARACTERIZATION OF VERMICULITE SAMPLES
                  FOR  FIBER CONTENT AND ASBESTOS CONTAMINATION
                                       by

                               Gaylord  R.  Atkinson
                                   Donna  Rose
                                   Ken  Thomas
                                   David  Jones
                                 E.  J.  Chatfield
                                  John  E.  Going
                                     TASK 32
                                  FINAL REPORT

                               September 27, 1982

                        EPA Prime  Contract No.  68-01-5915
                           MRI Project No.  4901-A32
                                  Prepared  for

                     U.S. Environmental  Protection Agency
                   Office of Pesticides  and  Toxic  Substances
                             Field  Studies Branch
                               401 M Street,  S.W.
                            Washington,  D.C. 20460

                   Attn:  Dr. Frederick Kutz, Project  Officer
                         Mr. Thomas Dixon, Task Manager
MIDWEST RESEARCH INSTITUTE  425 VOLKER BOULEVARD. KANSAS CITY. MISSOURI 64110  •  816753-7600

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                            DISCLAIMER

     This docuoent has been reviewed and approved for publication
by the Office of Toxic Substances, Office of Pesticides and Toxic
Substances, U.S. Environmental Protection Agency, according to the
Agency's peer review aystea.  The use of trade names or commercial
products does not constitute Agency endorsement or recommendation
for use.

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                            DISCLAIMER
                         4
     This document has been reviewed and approved for publication
by the Office of Toxic Substances, Office of Pesticides and Toxic
Substances, U.S. Environoental Protection Agency, according to the
Agency's peer review systeal.  The use of trade names or commercial
products does not constitute Agency endorsement or recommendation
for uae.

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                                   PREFACE

     This final report presents the results obtained on MRI  Project No.  4901-A,
Task 32, "Collection,  Analysis and Characterization of Vermiculite Samples for
Fiber Content and Asbestos Contamination."  The task was undertaken for the
Environmental Protection Agency under EPA Contract No. 68-01-5915 with Midwest
Research Institute.   Sample collection was conducted by MRI, Mr.  Kenneth Thomas,
sampling crew chief.  The analytical portion of this task was conducted through
subcontracts with Ontario Research Foundation,  Dr. E. J. Chatfield, Project
Manager, and IIT Research Institute, Mr.  David  Jones, Project Manager.  This
report was prepared by Mr. Gaylord R. Atkinson, MRI Task Leader,  with assis-
tance from Mr. Thomas, Dr. Chatfield, Mr. Jones, and Ms. Donna Rose (MRI).
                                        MIDWEST.RESEARCH INSTITUTE
                                             E. Going
                                        Program Manager
Approved:

         • Jl.
James L. Spigarelli, Director
Analytical Chemistry Department
                                     ii

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                                  CONTESTS

                                                                           ii
Preface .........................    .......    iv
Figures ........................  '.'.'.'.I....     v

Abbreviations, Definition!, and Specifications .............  vl

     1.  Introduction ..................... '*'!'..     3
     2.  Suanary  ............................      9
     3.  Experimental Protocol  .....................     9
               Saople collection  ....................     
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                                   FIGURES

Number                                                                   p*o«
    	                                                                   * O *a _

   1      Wind rose pattern showing the direction and intensity of the
            wind during the air sampling period at the Grace,  Libby,
            Montana, facility	   16

   2      Map of the Grace, Libby,  Montana,  facility showing the
            stationary air sampling locations	   17

   3      Wind rose pattern showing the direction and intensity of the
            wind during the air sampling period at the Grace,  Enoree,
            South Carolina, Mill	   22

   4      Map of the Grace, Enoree, South Carolina,  mill  area  showing
            the stationary air sampling locations	   23

   5      Wind rose pattern showing the direction and intensity of the
            wind during the air sampling period at the Grace,  Enoree,
            South Carolina, mine	   24

   6      Map of the Grace, Enoree, South Carolina,  mine  area  showing
            the stationary air sampling locations	   25

   7      Wind rose pattern showing the direction and intensity of the
            wind during the air sampling period at the Patterson,  Enoree,
            South Carolina, facility 	   28

   8      Map of the Patterson,  Enoree, South Carolina, facility showing
            the stationary air sampling locations	   29
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                                     iv

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                 TABLES (continued)                                           c
Number
17
18

19
20

21
22

23
24
25
26
27
28
29

30
31

32
33

34
35

Composition of Sanple 259-1 	 ,
Summary of Electron Microscopy Results
Grace, Grade 3 	 ,
Composition of Sample 282-1 	 ,
Summary of Electron Microscopy Results
Grace, Grade 4 	 ,
Composition of Sanple 264-1 	 ,
Summary of Electron Microscopy Results
Grace, Grade 5 	 ,
Composition of Sample 267-1 	 ,
Composition of Sanple 291-1 	 ,
Summary of Electron Microscopy Results
Grace, Head Feed 	 ,
Composition of Sanple 294-1 	 ,
Summary of Electron Microscopy Results
Grace, Extractor 	 ,
Composition of Sample 297-1 	
Sumaary of Electron Microscopy Results
Grace, Mill Dust 	
Composition of Sample 288-1 	
Summary of Electron Microscor/y Results
Grace, Screening Dust 	
Composition of Sample 430-7 	
Summary of Electron Microscopy Results
South Carolina, Grace, Grade 3. . . .
Composition of Sample 433-1 	
Summary of Electron Microscopy Results


for Sample Libby,


for Sample Libby,


for Sanple Libby,



for Sample Libby,

for Sample Libby,

for Sample Libby,


for Sample Libby,


for Sample Enoree,


for Sanrole Enoree.
Page
42

43
44

45
46

47
48
49
50
51
52
53

54
55

56
57

57
58

South Carolina, Grace, Grade 4	    59
                         vi

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                                                                                       t)

                           TABLES (continued)                                          °

                                                                       Page

36      Composition of Saaple 427-1 	    60

37      Summary of Electron Microscopy Results for Sample Enoree,
          South Carolina, Grace, Grade 5	    61

38      Composition of Sample 436-1 	    62

39      Summary of Electron Microscopy Results for Saaple Enoree.
          South Carolina, Head Feed + 100 Mesh	    63

40      Composition of Saaple 439-1 	    63

41      Summary of Electron Microscopy Results for Sample Enoree,
          South Carolina, Grade 3, Commercial Exfoliation 	    64

42      Composition of Sample 442-1 	    65

43      Composition of Sample 573-1 	    66

44      Summary of Electron Microscopy Results for Sample Enoree
          South Carolina, Patterson,  Ungraded	        67

45      Results of the Phase Contrast Analysis of Air Samples
          Collected at Three Vermiculit.- Sites	      68
                                  vii

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                                                                                          10
               ABBREVIATIONS, DEFINITIONS, AND SPECIFICATIONS

     The following are special terms or specifications that are used in this
report.

     1.  Venaiculite - A naturally occurring hydrated laminar mineral silicate.
Due to layers of water of hydration between the laminae, the vermiculite ex-
foliates or expands when heated.

     2.  Beneficiation - The process of obtaining vermiculite particles from
the ore.

     3.  Vermiculite grades - W. R. Grace, the largest U.S. vermiculite pro-
ducer, separates the beneficiated vermiculite into five size grades.  Grade 1
is the largest; Grade 5 the smallest.  Company grade specifications were not
obtained, but the following size data were determined by examination of the
five grades from Libby, Montana.  The data are presented as an indication of
differences among the grades.

               Approximate
                 maximum            Approximate
                dimension            number of           Approximate weight/
                  ("•»-'              particles/g           average particle

  1                5-10                   23                  42 mg
  \                3'5                   130                  7.4 mg
  I              n J-3                 1,700                  0.58 mg
  4              0.5-1                11,000                  91 ug
  5              0.2-0.5             130,000                  7.6 pg

     4.  Asbestos - A general term for a number of naturally occurring fibrous
mineral silicates.  Asbestos falls into two major classes, the serpentines and
amphiboles.  Chrysotile is the generally encountered serpentine.  The various
amphiboles are not easily identified using the electron microscope, and the
entire group is generally reported as "anphiboles" from the EM analysis.
(With greater effort the chemical composition can be determined with the  mi-
croprobe.)

     The major fibers identified by optical microscopy in this study were
amphiboles of the tremolite/actinolite series.  Tremolite and actinolite  dif-
fer by the ratio of iron and magnesium in the molecule, which results in  a
range of refractive indices.  The series is coaprised of a continuous varia-
tion with an arbitrary division between the two.   The composition of tremolite
ranges from Ca2MgsSi022(OH)2 to Ca2Mg4FeSi8022(OH)2 and that of actinolite
ranges from Ca2Mg4FeSi8022(OH)2 to Ca2MgFe4Si8022(OH)2.   Any composition  within
this series is often reported simply as "tremolite/actinolite."


                                    viii

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EM - Electron microscpy

TEM - Transmission electron microscopy

SAED - Selected area electron diffraction

JCPDS - Joint Committee on Powder Diffraction Standards

MRI - Midwest Research Institute, the prise contractor.

IITRI • IIT Research Institute
        10 W. 35th Street
        Chicago, Illinois 60616

ORF - Ontario Research Foundation
      Sheridan Park Research Community
      Mississauga, Ontario, Canada L5K 1B3
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                                     ix

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                                .  SECTION 1

                                INTRODUCTION

      In December  1978, the veraiculir.e industry subnitted information to the
EPA  regarding health problems experienced by employees who were processing
asbestos-contaminated veraiculite.  The original subaission indicated that
bloody pleural effusions had been detected in 4 of 350 eaployees; symptom-
atology and clinical findings in the eaployees were siailar to those found
in individuals with asbestos-related diseases.  Subsequent follow-up studies
by the Occupational Safety and Health Administration (OSHA) revealed an even
higher prevalence of health problems among the employees.

     Veraiculite, mined in the United States since 1929, is a hydrated
magnesium-iron-aluminum silicate and is often contaminated with asbestifora
minerals.  After mining, veraiculite is processed to remove impurities; how-
ever, some impurities, including asbestos, may remain in processed veraicu-


     Although vermiculite may contain fibrous materials, the health effects
from vermiculite itself are unknown.  A priority review of asbestos-
contaminated vermiculite, completed by the Office of Testing and Evaluation
in June 1980, suggested that the asbestos in veraiculite may be responsible
for the reported adverse health effects,  and it concluded that cerUin infer-
maf t /\« AanriMAA.J.«*a*.AV^fJ11__i«_^^       ,   *   .     .       w^^»*» **,u *u*. v&
                                       in in-depth risk assessment on vermicu-
     The available information on the composition of commercial vermiculite
indicated that asbestos contamination of venniculite does occur but that the
degree and kind of contamination might be difficult to assess and might varv
with the source of the vermiculite.   Therefore,  the objective of thif ulk*
was to sample and analyze vermiculite to deteraine the contaminants,  particu-
          anK °f "b?8ti5°™ »in«als present.   The study nS 2'pS3d
            to be used in the assessment of the  risk to the  population ex-
                                 • vermicullt" at cacb of the
     The original task objective was divided  into  two phases.  The first chase
was to conduct an in-depth analysis  of fibers present in,  and associated wUh
vermiculite ore concentrates and beneficiated veraiculite  from the major
££ >C«f  %mineY?Kt5eiJnit^d States and be"fi«=iated venniculite from the
?Sp L^nH  J7'  Bothbuik and air saraPlefl wre  to be collected and analyzed.
The second phase was to have been a  similar analysis of bulk and air samples
from a representative number of exfoliation plants in the  United States.  Be-

Thelask J.^if'ijVf10^"",:1*11111 EPA' thC 8COpe °f thC ta8k «« "ducel.
The task was limited to the collection of air and  bulk samples from three U S
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 mines  (W. R.  Grace in Libby, Montana; W. R. Grace in Enoree, South Carolina:              0
 and Patterson in Enoree, South Carolina).  The air samples were analyzed only            »
 by phase contrast microscopy, and the originally planned electron microscopic
 analysis was  omitted.

     With the reduction of effort, a set of the bulk samples that was con-
 sidered to be representative of each nine was selected as "priority" samples
 for i mediate analysis.  This set included the head feed for the ore process-
 ing mill and,  where size grades were produced, the smallest and mid-size
 grades.  This  set, representing seven samples, was analyzed by various tech-
 niques including electron microscopy for fiber content, with emphasis on as-
 Destifonn minerals.  The analysis was done by two independent laboratories.
 It  was considered possible that fibers could be bound between the veraiculite
 plates and that fiberb could be released with exfoliation.   Therefore, analy-
 ses were conducted both on the samples as received and after laboratory ex-
 foliation.  Laboratory exfoliation differs from conoercial exfoliation in that
 under the conditions of commercial exfoliation ouch of the fines and heavies
a"Jf!?OVe  5r0ffl thc vcrBic«lite-  The laboratory exfoliation is  done under
conditions that produce no sample fractionation.   Thus,  much of the asbestos
would be removed from the vermiculite during coamercial  exfoliation, but none
would be removed during laboratory exfoliation.

»».  jTh? *nalv8es of these samples were in various stages  of completion when
the decision was made to reduce the scope of the  task.   Analytical  results

rll^l f   \{  e!i?eriin"tal ™*°4*> sampling,  sample handling,  analyt-
ical results, and appendix.   Three additional  volumes  of  appendices  contain
the detailed analytical results.

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                                  SECTION 2

                                   SUMMARY

     In December 1978, the vermiculite Industry suboitted iofonutlon to EPA
regarding the health problems experienced by employee! who were processing
asbestos-contaminated vermiculite.  A priority review of asbestos-contaminated
vermiculite, completed by the Office of Testing and Evaluation in June 1980,
suggested that asbestos in vermiculite may be responsible for the reported
adverse health effects, and it concluded that certain information gaps needed
to be filled before an in-depth risk assessment of veraiculite could be ini-
tiated.

     The objective of this task was to develop the protocol and to conduct
sampling and analysis to determine the composition of veroiculite with empha-
sis on the content of asbestiform minerals.

     The original scope of the study included two phases.  The first phase
was for the collection and analysis of air and bulk samples associated with
vermiculite ore and beneficiated vermiculite from the four major U.S.  mines
and ports of entry.  The second phase was for a similar effort for a repre-
sentative number of exfoliation plants.

     Due to priority shifts within EPA,  the second phase was not undertaken
and the scope of the first phase was reduced.   Three mines and benefication
plants were sampled and the samples analyzed,  but the scope of the analysis
was reduced from the original protocol.   The air sample analysis was limited
to phase contrast optical microscopy for a selected set of the samples,  and
the electron microscopic analysis of the air samples was not performed.
* <    /nn    8amPles were analyzed by optical  microscopy and  x-ray dif f rac-
i!crL™)rS^t5e d?u8i
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        TABLE  1.  SUMMARY OP OPTICAL MICROSCOPY/XRD ANALYSIS RESULTS
                                                                                          e
                                                                                          tt
                                                                                          o
Sample3
Libby Grace
Grade 1, 270-1
Grade 2, 276-1
Grade 3, 259-1
Grade 4, 282-1
Grade 5, 264-1
Grade 5 (1-day), 267-1
Head feed, 291-1
Extract, 294-1
Baghouse mill, 297-1
Screen plant, 288-1
S.C. Grace
Grade 3, 430-1


Grade 4, 433-1


Grade 5, 427-1


Mill feed (+100 mesh),
436-1

Grade 3, expanded, 439-1


Grade 4, expanded, 442-1

S.C. Patterson
Ungraded, 573-1


Fibrous
Estimated
mass, %

4-6
4-7
2-4
0.3-1
2-4
2-5
21-26
1-4
8-12
2-5
t
< lb

t
< lb

v
< lb


< 1
v
< lb

v
< lb


< 1


phases
Mineral
types

Tren-actin
Trem-actin
Trem-actin
Trea-actin
Trea-actin
Trea-actin
Trem-actin
Trem-actin
Trem-actin
Trea-actin

Mixed
Anthopbyllite
Trem-actin
Mixed
Anthophyllite
Trem-actin
Mixed
Anthophyllite
Trem-actin
Mixed
Anthophyllite
Trem-actin
Mixed
Anthophyllite
Trem-actin
Mixed
Anthophyllite
Trem-actin

Mixed
Trem-actin
Anthophyllite
Nonfibrous
Estimated
oas*j^%

1-3
3-5
< 1
1-3
2-5
4-8
< 1
6-9
1-3
2-6
1-4

2-4
< 1

1-3
1-4

4-6
2-4

1-3
6-9

< 1
< 1

< 1
0.5-1


4-8
3-12

aophiboles
Mineral
types

Trea-actin
Trea-actin
Trem-actin
Trea-actin
Treo-actin
Trea-actin
Anthophyllite
Trea-actin
Trea-actin
Trea-actin
Trea-actin

Trem-actin
Anthophyllite

Anthophyllite
Trem-actin

Anthophyllite
Treo-actin

Anthophyllite
Trem-actin

Anthophyllite
Tren-actin

Anthophyllite
Trem-actin


Anthopbyllite
Trea-actin

a  With the exception of Sample No.  267-1,  all results are for composite
     samples.


b  Fiber bundles were mixed phase materials—both anthophyllite and
     tremolite-actinolite were present.

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 analyses  of  samples nearly completed.  The analysis data are coaplete free                °
 Doth  laboratories for the seven priority samples, but the data say or «ay not
 be  complete  for the others.

      A difference in the interpretation of the analytical protocol resulted
 in  a  variation in the counting procedure.  The requirement to count 100
 fibers was interpreted by ORF to mean 100 asbestifora fibers, while IIIRI
 counted 100  particles, defined as fibers by their aspect ratio of equal or
 greater than 3.  To check the significance of this counting variation, two
 samples with different fiber characteristics (the grade 5 samples fron Libby
 Montana, and Enoree, South Carolina) were selected for each laboratory to re-
 peat  the analysis using the alternate procedure.  Table 2 is a sioaary of the
 TEM analysis of the selected samples and includes the number and parts per
 million of fibers as determined by the two laboratories.

     The results suggest that there are more asbestifora fibers associated
 with  the smaller size grades of venniculite than with the larger gradao.  Both
 dust  samples collected at Libby were found to have a very high aamhibole con-
 tent and indicate that considerable asbestos is removed froa the vemiculite
 during beneficiation.   The South Carolina vermiculite appears to contain aub-
 stantially less asbestiform fibers than does that fron Libby, Montana.

     Table 3 is a summary of the phase contrast results of the air sarnies.
Only one of  the analyzed air samples exceeded 2.0 fibers/cc.  However, the
 rainy weather conditions at the time of sampling for all three locations
might have resulted in lower than normal fiber counts.

     Given the expected variability of the method, IITRI and ORF results ap-
pear to be in general  agreement.

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TABLE 2.  SUMMARY OF ELECTRON MICROSCOPY ANALYSIS
a Priority1"
Sample sample
Libby Grace
Grade 1
270-1
Grade 2
276-1
Grade 3 P
259-1
259-0
259-1
259-0
Grade 4
282-0
282-1
282-0
Grade 5 P
264-1
264-0
264-1(0)
264-0(1)
264-1
264-0
264-1(0)
264-0(1)
Head feed P
291-1
291-0
291-1
Extractor
294-1
Mill dust
297-0
297-1
Screening dust
288-0
288-1
Analysis,
exfoliated
no






X
X



X



X
X
X
X

A
X
X



X

X

ye«


X

X



X
X


X
X





X
X
X
X

X

X

X

X
Asbestifora fibers, all
Amphibole
Fibers/g Mass
x 106 (ppo)


31.6

23.4

38.9
25
42.0
59

1
65
1.8

118
100
127
98
142
160
119
110
62.5
130
73.8

55.0
100
777
300
1,800


78

48.5

210
59
250
240

1
460
17

840
600
1,200
570
2,600
1,800
350
2,600
670
690
590

420
4,600
35,000
3,000
41,000
lengths
Chrysotile
Fibers/g Mass
x 10« (ppa)


0.9

0

0.9
< 2.1
0.4
< 1


0
< 0.4

—
< 1.4

—
m
< 1.6
< 1.6
1.4
1.2


0.7
•
-
< 1.6



3.5 x 10"3

0

0.01

6.1 x 10"3



0


.
—

_
m
-
0.13
< i


3.4 x 10"3

-
_
.
I
u
0
B
                                             (continued)

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                        TABLE 2 (continued)
a Priorityb
Sample sample
S.C. Grace
Grade 3 P
430-1
430-0
430-1
430-0
Grade 4
433-1
433-0
433-1
433-0
Grade 5 P
427-1
427-0
427-1(0)
427-0(1)
427-1
427-0
427-1(0)
427-0(1)
Head feed P
436-1
436-0
436-1
Grade 3 exfoliated
Analysis,0
exfoliated
no


X
X



X
X



x
X
X
X


X
X

yes



X
X



X
X


X
X
X
X

X

Asbestifonn fibers, all lengths
Amphibole
Fibers/g
x 108


1.0
2.7
3.1
2.4

1.6
2.7
3.1
2.7

0.6
17
3.0
31
3.5
2.9
3.2
2.4
0.3
12
1.3

Mass
(PP«)


0.55
< 1
3.7
1

6 5
W • J
35
1.4
2

1 5
!> • J
37
4.8
130
4.1
120
7 3
1 • eficiated
Ungraded
  573-1
  573-0
  573-1
  573-0
                        X
                        X
                             X
                             X
                                      11.7
0.03  3.7 x 10'4  0.03   1.4  x  10~4
1-7       27    < 0.3        -    .
°-5        3      0.2    5.3  x  10"3
1.1        4    < 0.3
t«T ??i,T0"  5°™Swin8 the Banple nufflber indicates the analyzing labora-
tory, IITRI  and ORF,  respectively.  The "(I)" and "(0)" indicate! the
                                                                   the
      h«        W"e desi«Mted " Priority
     the tine  the program wag reduced in scope
                                               for complete  analysia at
       ?!"  CODSc^d on,.the «««Ple» " received and following laboratory
                         c««ercial exfoliation,  doea  not caV ...pi?

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        TABLE  3.   RESULTS OF THE PHASE CONTRAST ANALYSIS OF AIR SAMPLES
                    COLLECTED AT THREE VERMICULITE SITES
Sample
Libby, Grace
106 Field blank8
133 Field blank8
131 Front loader
148 Pit haul driver
138 Mine analyst
141 Bottom operator
130 No. 2 operator
139 Dozer operator
101 Shuttle truck
104 Screening plant, DW
111 Screening plant, DW
108 Trailer court
136 No. 5 substation
South Carolina, Grace
312 Field blank8
346 Field blank8
340 Mill monitor
321 Mill lab technician
301 Dragline operator
347 No. 4 bagger
330 No. 3 bagger
328 Mill (ENE) downwind
335 Mill (N) crosswind
307 Mine (N) crosswind
323 Mine (E) downwind
338 Mine (W) upwind
310 Truck driver
300 Screening plant floor
South Carolina, Patterson
505 Field blank8
533 Field blank8
508 Payload operator
520 Plant foreman
542 Bagger/forklift
513 (KE) downwind
506 Control off-site
515 (SE) crosswind
528 (SW) upwind
Saaple
vol. (£)

—
„
303
297
294
276
285
270
385
390
368
169
111.

-
340
478
240
314
285
287
80
291
154
264
257
354

255
252
249
188
274
299
147
Fibers/cc
ORF

< 0.02
0.03
0.02
< 0.01
1.5
1.2
3.1
0.02
0.1
0.08
0.1
0.03
0.03

< 0.02
< 0.02
0.03
0.07
< 0.01
0.06
0.1
0.05
0.04
< 0.01
0.01
0.03
< 0.01
0.06

< 0.02
< 0.02
< 0.01
0.01
< 0.01
< 0.01
< 0.01
0.01
0.02
i mi

0.04
0.05
0.04
0.01
1.9
• • 7
0.4
9.7
9 • 1
0 2
V • At
0 2
V • &
0 5
W • J
0.02
NDB
0.02

0.04
0 02
W • Wfc
0.03
o-2.
NDB
0 1
V • A
0 OS
W • V^
0.04
mr
fvV
0.02
0.02
0.01
0.3
0.14

< 0.01
0.02
0.04
01
. 
-------
                                  SECTION 3

                            EXPERIMENTAL PROTOCOL

     A study protocol was prepared for the task and reviewed by EPA and the
subcontractors before sampling and analyses were undertaken.  Appropriate
modifications were made following additional reviews.   The protocol "Task 32
Study Protocol for the Collection and Analysis of Vermiculite and Related Sa*
pies for the Evaluation of Fiber Content with Emphasis on Asbestiform Fibers"
appears in this volume as Appendix A.  A detailed analytical procedure for
bulk samples prepared by IITRI appears as Appendix B.

     During the program some modifications from the study protocol were found
to be necessary or desirable, and minor changes were made.  This section dis-
cusses the general protocol briefly, with major emphasis on areas where modi-
fications were made.

SAMPLE COLLECTION

     No najor changes were made in the saapling protocol.  The following
items are noted:

     1.  W. R. Grace representatives would not allow MRI personnel into any
of the processing facilities.  All samples, both bulk  and air, from within
the processing facilities were collected by EPA personnel.

     2.  Ore processing at Libby, Montana, involved a  wet beneficiation pro-
cess, while both facilities in South Carolina used dry beneficiation processes.
The differences in processes resulted in different types of waste materials.

     3.  W. R. Grace has automatic sampling equipment  at various places in
their processing for their QA program.  Portions of these samples were ob-
tained that represented 7 to 10 days of operation before our sampling.  One
day of automatic sample collection was observed by the sampling crew EPA reo-
resentative.                                                               *

SAMPLE HANDLING

Bulk Samples

     The bulk samples were packed in double sealed bags in the field and
shipped by air freight to MRI.   The increment samples  were riffle divided,  and
approximately equal portions of each increment of the  same sample type were
combined, mixed, and riffle divided to obtain replicate composite samples  for
analysis.                                                            *

-------
Air Samples

     The air sample filters were retained in the filter cartridges during
transport to MRI.  The plugged cartridges were placed in a special container
to maintain the filters in a horizontal position with the collecting surface
up and hand-carried back to MRI.  At MRI the filters were cut into three
equal portions and each portion individually taped to the bottoa surface of a
49 x 9 wm Milliporeft plastic petrie dish.  A set of one-third of each air sta-
ple filter was hand-carried to the two laboratories for analysis.

SAMPLE ANALYSIS

Bulk Sample Analysis

     Since no microscopy technique is capable of aeaiureaent over the whole
size range of fragments present in vermculite samples, it is of extreme impor-
tance, prior to selection of the analysis procedure, to understand precisely
now the analytical results are to be applied.

     The basic choice in the analysis of vermiculite was either to completely
pulverize the material and reduce the particle sizes into a range suitable for
a single analytical technique, or to retain the original size distribution and
measure relevant parameters on the material as normally used.  Using the lat-
ter approach, numerical fiber counts per unit mass of original material are
meaningful and assist interpretation on the basis of current medical opinion
that fiber numbers are the important exposure criterion.

     If the material is completely crushed, there are a number of disadvantages:

     1.  The fiber size distribution is not preserved, and any numerical fiber
count is meaningless except that fiber volume can be considered as an indica-
tion of the mass percentage of fiber in the original sample material.

     2.  Even the mass value thus obtained is not representative of that in
the final product, since at exfoliation much of the massive material is sepa-
rated and discarded.

     3.  Simple X-ray diffraction (XRD) measurements of the amphibole or ser-
pentine content of such a pulverized sample is of inadequate sensitivity (about
 * 5?r ?mPhlb°les and possible 5% for serpentine).   Moreover, XRD is incapable
of distinguishing the fibrous varieties from other amphiboles or serpentine
1979).
     4.  The crystallography of the fibers  may be altered  (Spumy et al.,
     The procedure of Chatfield and Lewis  (1980)2 was  designed  to  retain  the
size distribution of the material as it is noraally used, and to allow venT
(sensitive oeasureoent of asbestos fiber concentrations down  to  detection  lim-
its in the parts per million (ppm) region.
                                    10

-------
                                                                                         c
                                                                                         TJ
     Essentially, their procedure was:                                                   °

     1.  To suspend the beneficiated venniculite in water and sample, for
transmission electron microscope (TEM) analysis, only the range of particle
sizes which would include all respirable fibers.

     2.  To simulate on a laboratory scale the industrial exfoliation proce-
dure, and to examine by TEM the fraction which does not float on water.  The
floating fraction would in fact be the final product.  If fibers have been
found in the earlier analyses, the floating fraction could also be examined to
determine its fiber content.

     3.  To examine typical venniculite flakes for the presence of intercalated
fibers which may be released on exfoliation.

     If there are no very large fibers present, the assumption can be made
that any fibrous component has been sampled representatively from the aqueous
suspension, and the results can be interpreted as total fiber concentrations
by weight.   Where large amounts of asbestos fibers are present throughout the
whole size spectrum, the procedure introduces a size cut-off above which no
particles are included in the analysis.  Under these conditions the concentra-
tion by weight must be interpreted carefully, although concentrations by number
will be almost unaffected.  It is important when using this method that the
size cut-off established does not restrict the representative sampling of the
largest fibers considered to be respirable.  Timbrell (1965)3 has determined
that the free falling speed of high aspect ratio fibers is proportional to the
square of the diameter and only increases slowly with length.  The largest
compact particles normally found in lungs are about 10 micrometers (pm) in
diameter (unit density), which as a first approximation was found to be equiv-
alent to a fiber of about 3.5 \im in diameter, whatever its length may be.
Hence, the size cut-off in the analytical method should exceed a unit density
equivalent spherical diameter of 10 \tm, which corresponds to a sphere of 5.6
Mm diameter if the density is assumed to be 3.2 g/cm3.  The falling velocity
of a sphere is obtained from the Stokes' relationship:

                    v = g'd2 (ps - pL)
                             18n

     where  V = terminal velocity
            g = acceleration due to gravity
            d = diameter of the sphere
           ps = density of the sphere
           pL = density of the liquid
            H = coefficient of viscosity of the liquid

     For a sphere of 5.6 \m diameter and density of 3.2 g/cm3 the terminal
velocity in water is calculated to be 0.0037 cm/sec, or 270 sec/cm.  Under the
agitation conditions in the ultrasonic bath, it is unlikely that particles of
this low falling velocity will deposit during the period when representative
samples of the dispersion are withdrawn for analysis.  Accordingly, it can be
stated that the method yields a fiber count which includes all fibers consid-
ered to be respirable.
                                    11

-------
                                                                                         I
                                                                                         t)
     The analytical procedure described above does  not  yield  an  actual  total              °
fiber content by weight where very large fibers  are present,  and it  is  for                n
this reason that the initial step of a low oagnlfication optical exaaination
was incorporated.  In this way such stapled can  be  detected before effort is
expended on TEH fiber counts which nay be irrelevant.   However,  the  TEH proce-
dure must still be used if determination of the  respirable fiber concentration
is required.

     Both analytical laboratorieo contributed to the preparation of  the
adopted protocol and both laboratories followed  the protocol. However, there
were variations in emphasis and interpretation of the protocol by the two  lab-
oratories, and these differences were not recognized until toae  of the results
were obtained.  While to a degree the variations in procedures prevent the  di-
rect comparison of results, the slightly different  approaches coapleaent each
other and give a better overall understanding of the saaples  than would either
single approach.

     The significant differences were as follows:

     1.   ORF examined the bulk samples by optical microscopy  for the presence
and qualitative identification of asbestiform fibero.   IITRI  performed s»ore
complete qualitative and semiquantitative analysis  of the bulk saople using
density fractional separation, followed by component identification  by optical
microscopy and X-ray.

     2.   The following appeared in the protocol  for the TEM analysis:  "Make
fiber count - determine chrysotile or amphiboles.  Count 100  fibers  or 10
grids of 200-mesh screen.  Determine the limits  of detection  and count aore
grids if necessary."  ORF interpreted this statement to aean  count 100 chryso-
tile or amphibole fibers; IITRI interpreted the  statement to  mean count 100
particle unite with an aspect ratio of equal to  or greater than 3.  To deter-
mine the effect of the difference of counting procedure between the  two labor-
atories, two samples were selected for cross comparison.  For these  two saa-
ples each laboratory examined the sample by the  other's procedure as well  as
their own.  The two samples were selected to represent  a high and low concen-
tration of asbestiform fibers (Grade 5 from Libby and Grade 5 from South Carolina
Grace).

Air Sample Analysis

     Due to a change in the scope of the task, the analysis of the air sample
filters by TEM was not undertaken.  The optical  phase contrast analysis was
conducted according to the protocol.
                                    12

-------
                                                                                         E
                                                                                         •d
                                                                                         •o
                                                                                         n
                                  SECTION 4

                                  SAMPLING

     Sampling trips were made to the Grace mine and processing facilities near
Libby, Montana, during October 21-26, 1980, and to both the Grace and Patterson
mines and processing facilities near Enoree, South Carolina, during November
3-6, 1980.  Both air samples and bulk samples were collected at each location.
Air sampling was of two types, personal and stationary.  For the personal sad-
pies, nine Dupont Model 4000 samplers were used.  The flow rates were cali-
brated before and after sampling.  Stationary air sampling was conducted us-
ing battery-powered stationary samplers designed by MRI.  These samplers have
proven to be effective in previous air sampling projects.4'6'6  Wind condi-
tions during sampling were recorded using a Wang meteorological station.
Brief descriptions of sampling conditions and a list of samples collected fol-
low.

W. R. GRACE MINE, LIBBY, MONTANA

     Mr. Fred Eaton of W. R. Grace, Cambridge, Massachusetts, was the company
representative for the coordination of sampling.  Mr. Jim Salois of MSHA,
Helena, Montana, was present at the request of Ms. Diana M. Kraft, MSHA,
Arlington, Virginia.  Mr. Salois was familiar with the Libby facilities, and
his presence and suggestions were very helpful.

     At the request of Mr. Eaton, duplicate concurrent personnel air samples
were taken, one for this task and one for Grace.  Thus each subject was fitted
with two samplers.  Mr. Eaton also requested that all personal air sampler
pumps used for this task be recalibrated at the Libby facility even though
they had been calibrated just before shipment from MRI.  The nine pumps used
were determined to have flow rates ranging between 2.03 and 2.19 liters/min.
The flow rates for the stationary samplers were measured at the time the sam-
plers were set up, periodically during sampling, and at the end of sampling.
The specific flow rates, calibration data, and related information appear in
Appendix C of this report.

     Sampling was scheduled and conducted on Thursday, October 23, 1980.  For
several days prior to sampling the weather had been rainy, and sampling was
started in heavy fog with essentially no wind in the nine area.  There was no
evidence of dust in the mine, from either the mining operation or along the
truck routes.  The weather cleared shortly after noon.  The wind direction
and speed were recorded during the sampling day.
                                    13

-------
                                                                                         t
                                                                                         •a
     The objective was to take a short (2-hr) sanple,  followed by a  longer               o
(6-hr) sample that would complete the work shift.   The actual tines  varied               »
somewhat from the intended times, but the actual times and voluaes for each
sample were recorded (Appendix D).

     Grace has a routine bulk sampling procedure as part of their product
quality control program.  At our request they had taken and retained bulk
samples of the five grades of product plus related head feed, tailings, and
dusts for 7 to 10 days before air sampling.   The samples taken on October  23
were comparable to the earlier samples, but their collection was observed  and
verified by Tom Dixon of EPA.*  The air samples collected at Libby,  along  with
the approximate sampling duration, are given in Table  4.  Figures 1  and 2  show
the wind conditions and site positions for the stationary air samplers. The
bulk samples collected at Libby .ire given in Table S.

W. R. GRACE MINE AND PROCESSING MILL, ENOREE, SOUTH CAROLINA

     Mr. Fred Eaton, who was the company representative at Libby, Montana,
was also the company representative at Enoree.  Ore from two mines (Lanford
and Foster) are hauled to the processing mill at a third location.  During
the sampling period only the Foster mine was in operation.  The Foster mine
is located near the southwest corner of the junction of County Road  50 and
Interstate 26 in Spartanburg County.  The mill is located on Highway U.S.  221
bjout 1 mile south cf .the junction with Highway 92, in Laurens County.  The
initial schedule was to sample at the mine on Tuesday, November 6, 1980, and
at the mill on Weihesday.  However, because of rain during Tuesday morning,
the mine was closed and the schedule was reversed.  A light rain fell Tuesday
morning; the remainder of the sampling period was clear and cool.

     The air samples collected at the Grace Enoree operations are given in
Table 6 and the bulk samples are given in Table 7.  The wind conditions and
air sampling site positions are shown in Figures 3 and 4 for the mill and  in
Figures .S and 6 for the mine.

PATTERSON VERMICULITE COMPANY, ENOREE, SOUTH CAROLINA

     The Patterson mine and exfoliation/bagging operations are located approx-
imately 7 miles northeast of the W. R. Grace mill.  No mining was underway on
the day of sampling, November 6, 1980, so sampling was only conducted around
the processing plant.  Patterson does not size their product and produces  a
single size grade.  The air samples collected at the Patterson plant are
listed in Table 8 and the bulk samples in Table 9.  The wind conditions and
air sampling site positions are shown in Figures 7 and 8.
   MRI employees were excluded from all mill operations.
                                    14

-------
TABLE 4.  AIR SAMPLES COLLECTED AT THE GRACE MINE AND MILL. LIBBY. MONTAHA
Sample description
Pesonnel samplers
Front loader
Front loader
Pit driver
Pit driver
Mine analyst
Mine analyst
Mill operator, bottom
Mill operator, bottom
Mill operator No. 2
Mill operator No. 2
Bulldozer operator
Bulldozer operator
Shuttle truck driver
Shuttle truck driver
Stationary samplers
Station 7 screening plant D.W.
Station 7 screening plant D.W.
Station 7 screening plant D.W.
Station 7 screening plant D.W.
Station 6 screening plant U.W.
Station 6 screening plant U.W.
Station 2 perimeter D.W.
Station 2 perimeter D.W.
Station 2 perimeter D.W.
Station 2 perimeter D.W.
Station 4 perimeter C.W.
Station 4 perimeter C.W.
Station 5 lower meadow
Station 5 lower meadow
Station 9 trailer court
Station 9 trailer court
Station 8 car loading
Station 3 car loading
Station 3 "22" level dump
Station 3 "22" level dump
Station 1 substation No. 5
Station 1 substation No. 5
Field blanks




Filter
No.

131
135
148
126
138
129
141
146
130
125
139
128
101
121

104
111
112
120
116
124
109
113
145
147
103
149
119
115
108
102
123
122
107
134
136
132
114
137
106
133
110
Approz,
tisw
(hr)

2
5
2
5
2
5
2
5
2
5
2
5
2
7

2
2
6
6
2
6
2
2
6
6
2
2
2
6
2
6
2
3
2
6
2
6





Analysis
assignment
PC EM Hold

X
X
X
X
x
x
x
x
X
x
x
x
x
X

x
x
x
x
x
x
4\







V
A
x
A


x
A
X
X
X
X
X
a  PC - phase contrast optical microscopy, EM
     Hold - sample retained without analysis.

b  Station numbers indicated in Figure 2.

                                     15
                                             -  electron microscopy,
                                                                                          C
                                                                                          -o
                                                                                          0
                                                                                          10

-------
          NV/
  WNW
  W
                   NNW
NNE
                                                   NE
                                          SSE
                                                          :i£
                                                    SE
                                                  32<* Calm
       '.Vlndi 0-3mph
Figure 1.  Wind  rose pattern showing the direction and intensity
        of the wind during the air sampling period at the
                 Grace, Libby, Montana, facility.
                                                                                      E

                                                                                      «
                                                                                      10
                               16

-------
                                                                                           E
                                                                                           •a
                                                                                           10
• A.  T  1-0  N_ A  L

._— .xi- v  « t ..v"  '• t ; *£

                                                    W.R. GRACE
                                                    VERMICUUTE MINE
                                                    U8BY. MONTAh4A-
                                                       • StaHonory Air
                                                      Monitoring Srotlont
  Figure 2.  Map  of the Grace,  Libby, Montana, facility showing
              the  stationary  air sampling  locations.
                                 17

-------
 TABLE 5.  BULK SAMPLES COLLECTED AT THE GRACE HIHE ASP MILL. LIBBY. MONTANA
    Sample description                                     No. of staples

Beneficiated Grade 1 vermiculite                                  lla
Beneficiated Grade 2 vermiculite                                  11*
Beneficiated Grade 3 vermiculite                                  11*
Beneficiated Grade 4 vermiculite                                  lla
Beneficiated Grade 5 vermiculite                                  11*
Dust from screening plant                                          8^
Dust from dryer                                                    9C
Head feed                                                          9C
Under 90 mesh                                                      9C
Coarse tails                                                       9C
Extractor                                                          9C

a  Days collected for 11-day samples:  October 7, 8, 9, 10, 13, 14, 15, 16,
     17, 21, 23, 1980.                             .ft,,,,
b  Screening plant dusts collected:  October 8, 9, 10, 13, 14, 15, 17, 23,
     1980.
c  Collected October 8, 9, 10, 13, 14, 15, 16, 17, 23, 1980.
XT
                                     18

-------
TABLE 6.  AIR SAMPLES COLLECTED AT GRACE, ENORBE,  SOUTH CAROLINA
                                                                                    E
                                                                                    •d,
                                                                                    •0,
Sample description
Mine personnel sanies
Truck driver 1
Truck driver 1
Truck driver 2
Truck driver 2
Dragline operator 6
Dragline operator 6
Mine stationary saoples
Crosswind N. station 1
Crosswind N. station 1
Crosswind S. station 3
Crosswind S. station 3
Upwind V. station 4
Upwind W. station 4
Downwind E. station 2
Downwind E. station 2
1 mile offsite station 5
1 mile offsite station 5
Along haul route
Along haul route
Mill personnel samples
Forklift operator
Forklift operator
Bagger
Bagger
Bagger
Bagger
Bagger
Bagger
Mill monitor
Mill monitor
Mill laboratory technician
Mill laboratory technician
Mill stationary samples
Mill office
Screening floor
Screening floor
Screening floor
Crosswind N. station 1
Crosswind N. station 1
Approx.
Filter tine
Mo. (hr)

315
324
310
320
301
306

351
318
307
353
316
338
323
352
334
350
331
354

305
339
314
322
330
349
347
337
336
340
308
321

304
300
332
341
345
343

2
2
2
5
2
6

5
4
2
5
4
2
2
6
2
5
2
5

2
4
2
4
2
4
3
4
3
3
3
4

7
2
3
1
2
5
Analysis
aisignaent
PC EM Hold

X
X
X
X
X
X

X
X
X
X
X
X
X
X
X
X
X
X

X
X
X
X
X
X
X
X
X
X
X
X

X
X
X
X
X
X
                                                       (continued)
                                19

-------
                             TABLE 6 (continued)
                                         f
                                         •d
                                         •0
                                         JO
Sample description
         Approx.     Analysis
 Filter   tine
	No.     (hr)    PC
Mill stationary samples (continued)
Crosswind N. station 1
Crosswind N. station 1
Crosswind S. station 3
Crosswind S. station 3
Upwind W. station 4
Upwind W. station 4
Downwind E. station 2
Downwind E. station 2

Offsite control

Field blanks
   328
   313
   342
   326
   344
   309
   335
   302

   329

   312
   346
   319
   348
   327
2      X
5
5
2 (void)

5
2      X
5
       X
       X
X
X
X

X

X
                                                                       X
                                                                       X
a  *'C - phase contrast optical microscopy, EM - electron microscopy,
     Hold - sample retained without analysis.

b  Station numbers indicated in Figure 4.
                                     20

-------
                                                                                         V
                                                                                         id
                                                                                         10
        TABLE 7.  BULK SAMPLES COLLECTED AT THE PATTERSON OPERATIONS                     »
                           ENOREE, SOUTH CAROLINA
	Sanple description	No. of sanples

Raw ore from stockpile                                            1

Raw ore prescreening hopper                                       1

Postscreen ore                                                    3a

Dried ore                                                         4a

Exfoliated final product                                          4a

Waste from screening                                              4*

Waste from exfoliater                                             4*
a  Samples were collected at approximately 2-hr intervals.
                                      21

-------
                                                                                  E
                                                                                  •d
                                                                                  10
                                                                                  X
                  NNW
                                       NNE
        NW
WNW
                                                        ENE
WSW
     Wlixb 4-7mph

     Winds 0-3mph
                 SSW
                                        SSE
23% Calm
 Figure 3.   Wind rose pattern showing the direction and
   intensity of the wind during the air sampling period
        at the Grace, Enoree, South Carolina,  mill.
                           22

-------
I   y/
Figure 4.  Map of the Grace, Enoree,  South  Carolina, mill area
        showing the stationary air sampling locations.
                             23

-------
                                                                           f
                                                                           •d
                                                                           to
             NNW
Figure 5.  Wind rose pattern showing the direction and
 intensity of the wind during the air saopling period
      at the Grace, Enoree, South Carolina, mine.
                         24

-------
                                                                                     t
                                                                                     rd
                                                                                     (0
^^•H
"~
Rood 50
/V
© ° if

-------
     TABLE 8.   AIR SAMPLES COLLECTED AT PATTERSON, ENORBE,  SOUTH CAROLIHA
                                                                                         C
                                                                                         rd
                                                                                         10
Sample description
Personnel samplers
Bagger/forklift operator


Foreman

Payload operator


Stationary samplers
Crosswind S.E. station 2
Crosswind N.W. station 4


Upwind S.W. station 3
Downwind N.E. station 1
Remote, control
Field blanks



Filter
No.

542
504
517
520
521
511
508
519
516

515
502
503
518
531
540
528
525
513
523
506
527
505
522
533
538
Approx.
tine
(hr)

2
3
3
2
3
3
2
3
3

3
6
2
6
2
6
2
6
2
6
2
6



Analysis
assignment
PC EM Hold

X
X

X
X
X
X
X
X

X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
a  PC - phase contrast optical microscopy, EM - electron microscopy,
     Hold - sample retained without analysis.

b  Station numbers indicated in Figure 4.
                                     26

-------
                                                                                         rd
                                                                                         io
         TABLE  9.   BULK SAMPLES  COLLECTED AT THE GRACE MIME AND MILL                      »
                           ENOREE, SOUTH CAROLINA
Sample description
Eeneficiated Grade 3 vermiculite
Beneficiated grade 4 verniculite
Beneficiated grade 5 venniculite
Dryer composite
Mill feed +100 mesh
Mill feed -100 mesh
Wet scrubber discharge composite
Composite total tails, November 5
Lanford Mine composite, November 5
Foster Mine Composite, November 5
Exfoliated Grade 4 "stabilized"
Exfoliated Grade 4 plain
Exfoliated masonry insulation Grade 3 "coated"
Exfoliated Grade 3 plain
	 No. of sajpples
7a
7a
7a
7a
7a
7a
lb
1
1
1
lc
lc
lc
1

3  Da^8£ollected for 7'day samples:   October 27, 28, 29, 30, 31, November 1,


b  Composite collection for October 28,  29,  30,  1980.

c  The exfoliated samples were saopled at the Kearney Expansion plant.
                                     27

-------
                                                                                      rd
                                                                                      10
                                           HNt
Figure 7.  Wind rose pattern showing the wind direction and intensity
          of the wind during the air sampling period at the
            Patterson, Enoree, South Carolina, facility.
                                28

-------
                                                                                               rd
                                                                                               10
                                                                                               X
                                    Mill and
                                    Packaging
                                    Operation
     ff
     I   I
     I   I
                •To Highway 221
Sketch of Pott«non V«rmlcullt«
(Sampled 11-6-80)

A Meteorological Station
Q Air Sampling Sratlon
  Figure 8.   Map of the Patterson, Enoree, South Carolina,
   facility  showing the stationary air sampling locations.
                                29

-------
                                                                                     rd

                                                                                     10

                                                                                     X
                                 SECTION 5


                              SAMPLE HANDLING
       1Thf tlle bulVaaple8 werc 8^PPed air freight to MRI  from the sampling
        The air samples were hand-carried and maintained in a horizontal,
 sample-up position.
BULK SAMPLES



* *nan°Stf **•
        **"*•
     n°Stf **• the oulk 8amPles were collected as increment  samples representing
     Jh! **"*•.*»*•«** •«*!« were prepared for this  analysis.  To pre-  *

                                increment 8afflPle was 'i«led to obtain a rep-
 resentativrM       K
 If «rh T*J "         he increment-  Approximately equal weight fractions
 of each of the increments were combined to make a composite sample.  The com-

 t£ 5LSF   WaS . CD -?Xed and riffl£d t0 produce f°ur equal samples   Sne of
 anain rlffLTl     aside,and, retained " • control.   One of the fourths w^s
 ?fp« "ffjed 1° Produce two fractions, each one-eighth of the original sample
 These two fractions were combined with the other two  fourths to refult in the
 composite division into 1/4, 3/8, and 3/8 of the original composite   Tne

 tlie othlr «vS«WfB "tained at H*1' one "3/8" fracton was sen? to IITRI, and
 the other "3/8" fraction was sent to ORF for analysis.
              glvenln
AIR SAMPLES
cumference of the filter but  did not contact the  sampling portion of the fil-


£SJ^?.^.TMWS=a?,S14L-.W
one-third of each air sample  filter was hand-carried to IITRI in Chicaao
Illinois, and to ORF in Mississauga, Ontario.                    uucago,
                                  30

-------
                                   SECTION 6

                              ANALYTICAL RESULTS
          analytical  results  of  this  program  consist  of  findings  from (a)  the
     h 11,    Vy diffractio° (XRD)  data  and (b)  electron microscopy data for
 the bulk samples  and from the phase  contrast optical microscopy  data for  the
 air samples.   The detailed XRD  and EM data are  contained in  three volumes of
                       **** ** *** aPPendice8 are  referenced  for  each sample
 nt**"?  da-3  obtain?d  5or  the bulk samples, by IITRI  from the density  sepa-
 rated  fractions provided a  good overview of the  composition and complexity of
 the  samples.   These data, including weight  percent of three density  fractions,
 and  a  listing  of  identified mineral phases  in the various samples are  pre-
 sented  in summary at  the beginning of this  section.   This is followed  by the
 complete  results  obtained for individual samples.
 (TBE)!'  DeDSity 8reatCr than 2>9? 8/CC'
in TRF-c        I1"- tha° 2'97 and 8reater thflo 2.76, floats on TBE, sinks
in TBE/isopropanol mixture with density of 2.76 g/cc.

     3.  Density less than 2.76, floaU on 2.76 g/cc liquid.

     Table 10 is a list of selected related minerals and their densities
(specific gravity)   From these values it can be seen that the vSIlSlite
would be separated from most of the other materials, and that the materials
DercentDo?   ? T6™1""*™" be separated into'two fraction's,  ^weight
percent of materials in each density fraction of samples is given in Table
are llsteSln^hl^^8 idc?tifjed in each 8an>P^ fraction analyzed by XRD
are listed in Table 12.  A key is provided with this table which groups the
minerals according to types, and lists chemical formulas and JCPDS f ile card
numbers for the patterns which were used to identify the mineral species
The raw data obtained in the analyses appear in Appendix I       8Pecies-
                                                                                          I
                                                                                          rd
                                                                                          10
                                                                                          X
                                    31

-------
TABLE 10.  SPECIFIC GRAVITIES OF SELECTED MINERALS
                                                                              rd
                                                                              10"
__ Mineral
Venniculite
Biotite
Chrysotile
Serpentine
Talc
Anthophyllite
Actinolite
Tremolite
Fcrroactinolite
Curamingtonite
Grunerite
Diopside
Hornblende
Quartz
01 i vine
	 Cheaical fcmula 	
(Mg,Ca)0 3(Mg,Fe,Al)3 o(Al,Si)4010(OH)4
K(Mg,Fe)3(AlSi3010)(OH)2
Mg3Si206(OH)4
M83Si206(OH)4
Mg3Si4010(OH)2
(Mg,Fe)7Si8022(OH)2
Ca2(Mg,Fe)5Si8022(OH)2
Ca2Mg5Si8022(OH)2
Ca2FesSi8022(OH)2
(Mg,Fe)7Si8022(OH)2
Fe7Si8022(OH)2
CaMgSi206
(Ca,Na)2 3(Mg,Fe,Al)5Si6(Si,Al)2022(OH)2
Si02
(Mg,Fe)2Si04
Specific
travitv
.. . fll . HE — :
2.4
2.8 - 3.2
2.5 - 2.6
2.3 - 2.6
2.7 - 2.8
2.85- 3.2
3.1 - 3.3
3.0 - 3.2
3.2 - 3.3
3.1 - 3.3
3.6
3.2
3.0 - 3.4
2.65
3.27 - 4.37
                       32

-------
 TABLE 11.   DENSITY-SEPARATED (AND HAND-PICKED) FRACTIONS PRODUCED
-
wt %
a hand-picked
Sample fibers
Libby Grace
Grade 1, 270-1 4.5
Grade 2, 276-1 4 5
Grade 3, 259-1 i.o
Grade 3, 259-1 duplicate
Grade 4, 282-1 o.3
Grade 5, 264-1
Grade 5 (1-day), 267-1
Head feed, 291-1
Extractor, 294-1 i.o
Baghouse mill, 297-1
Screen plant, 288 I
S.C. Grace
Grade 4, 433-1
Grade 5, 427-1
Mill feed (+100 mesh),
436-1
Grade 3, expanded, 439-1
Grade 4, expanded, 442-1
S.C. Patterson
Ungraded, 473-1
Wt %
tetrabromoethane
sinks

9.8
12.2
9.1
8.7
10.9
17.2
26.7
55.8
10.5
2.7
3.5

3.9
10.9
26.3
0.2
* 0.4

18.1
Wt %
2.76
sinks

5.1
5.6
22.6
14.1
11.4
25.6
6.1
27.3
17.6
25.3

48.9
4.6
23.6
0.4
•v 0.4

13.9
Wt %
2.76
floats

85.1
82.2
68.3
75.0
71.4
47.8
38.1
62.2
79.8
71.2

47.2
84.4
50.1
99.4
* 99.2

68.0
                                                                                       n)


                                                                                       Io
                                                                                       JO
With the exception of Sample No. 267-1, all results are for composite
  samples.                                                     '
                                  33

-------
                       TABLE 12.  SUMMARY OF X-RAY DIFFRACTION ANALYSIS RESULTS
  Sample
    Fraction-Phase
    Mineral phases identified  fron XRD data
   	(exluding vermiculite)	
Libby Grace
  Grade 2,  276-1
  Grade 3,  259-1


  Grade 5,  264-1
 TBE-SINK-fibers
 TBE-SINK-milky, green
 TBE-SINK-dk.  green,  glassy
 TBE-SINK-lt.  green,  glassy

 TBE-SINK-fibers
 TBE-SINK-total

 TBE-SINK-fibers
 TBE-SINK-total
  Grade 5  (1-day), 267-1   TBE-SINK-fibers

                          TBE-SINK-total
 Head feed, 291-1
TBE-SINK-total

2.76 SINK-total


2.76 FLOAT-total
 Tremolite,  talc
 Tremolite,  talc
 Diopside, magnetite
 Diopside, magnetite

 Tremolite
 Diopside, sphene, augite, fluorapatite

 Tremolite,  diopside, sphene, talc, magnetite
 Diopside, treaolite, magnetite, fluorapatite,
  sphene, hematite, rhodonite

 Treaolite,  diopside, talc, sphene, augite,
  fluorapatite, quartz, magnetite
 Diopside, sphene, treaolite, augite, quartz,
  fluorapatite, magnetite, hematite

Diopside, treaolite, augite, fluorapatite,
  sphene, magnetite, hematite,  quartz
Biotite, treaolite, vermiculite-hydrobiotite,
  diopside, quartz, talc, fluorapatite, sphene,
  calcite, magnetite, hematite
Tremolite, diopside, quartz, vermiculite-
  hydrobiotite, calcite, fluorapatite, talc,
  antigorite

                            (continued)
                                                                                                      a 3 a

-------
                                          TABLE 12 (continued)
   Sample
    Fraction-Phase
    Mineral  phases identified  from  XRD  data
   	(exluding veraiculite)
 S.C. Grace
   Grade 3, 430-1
   Grade 5,  427-1
   Mill  feed, 436-1
S.C. Patterson
  Ungraded, 571-1
 2.76 SINK-total
                            2.76  FLOAT-nonmicaceous
 TBE-SINK-fibers
                           TBE-SINK-total
TBE-SINK-fibers

TBE-SINK-green, glassy
TBE-SINK-green, milky

TBE-SINK-colorless, glassy
TBE-SINK-total

2.76 SINK-total
 Sodium  tremolite,  hornblende, anthophyllite,
   talc,  vermiculite-hydrobiotite, fluorapatite,
   sphene,  calcite,  quartz
 Quartz,  microcline, albite, sodium trenolite,
   sphene,  vermiculite-hydrobiotite

 Tremolite, anthophyllite, sodium hornblende,
   vermiculite-hydrobiotite, talc, sphene,
   fluorapatite, albite, aagnetite
 Sodium hornblende,  treaolite, anthophyllite,
   fluorapatite, sphene, vermiculite-hydrobiotite,
   magnetite

 Sodium treaolite, anthophyllite, talc,
   hornblende
Hornblende, sodium tremolite, sphene
Sodium tremolite, hornblende, sphene,
   fluorapatite
Fluorapatite, anthophyllite, sodiun treaolite,
  hornblende
                                                        Trenolite, iron anthophyllite, sodium hornblende,
                                                          talc, fluorapatite, rutile, sphene, ugnetite
                                                        Talc, treaolite, anthophyllite, hornblende,
                                                          quartz, rutile, fluorapatite, veraiculite-
                                                          hydrobiotite
a  With the exception of Sample  No.  267-1,  all results are for composite saaples.
                                                                                                        8 3 S nt

-------
KEY TO TABLE 12
                                                             rd
                                                             10
                                                             X
Mineral name
Micaceous minerals
Verniculite
Biotite
Vermiculite-hydrobiotite
Amphiboles
Tremolite
Sodium tremolite
Anthophyllite
Iron anthophyllite
Hornblende
Sodium hornblende
Pyroxenes
Diopside
Acmite-augite
Serpentine
Antigorite
Iron oxides
Magnetite
Hematite
Others
Talc
Quartz
Microcline (feldspar)
Albite (feldspar)
Calcite
Fluorapatite
Sphene (titanite)
Rutile
Rhodonite
Chemical formula per JCPDS (file card
(Ng2.37Feo.37Xo.2e)(All.28Si2.72)09
-------
     The XRD data generally confirmed the mineral identification nade micro-
scopically.  The XRD data also confirmed the observation that partially al-
tered mineral phases-particularly altered biotite-vermvculite phases--were
present.  Since venniculite is generally formed as an alteration product of
bi.otite mica, it was not surprising to find the intermediate phase, mixed
layer vermiculite-hydrcbiotite material in most samples.

     The XRD analyses did provide some surprising results.  The most inter-
esting result was the abundance of vermiculite in the hand-picked fiber frac-
tion of the Grade 5 composite from Grace's South Carolina mine (MRI Sample
No. 427-1).  Microscopical examination of the ground material submitted for
XRD revealed that the vermiculite was intergrown with the amphibole fibers
and also did in fact occur in a pseudomorphically fibrous crystal habit.
Another rather interesting result of the XRD work was the identification of a
sodium-bearing fibrous tremolite phase in the South Carolina samples.

     Interpretation of the XRD data was hampered by the peak intensity altera-
tions caused by crystal preferred orientations.  Most of the mineral phases
had crystal morphologies with at least one exaggerated crvstallographic axis.
Thus, in preparing samples for XRD as thin films by filtration onto silver
membranes, the crystals tended to orient with the exaggerated crystal planes
parallel to the filter surface--!.e., venniculite plates and tremolite fiberc
landed on the filters lying flat, rather than on end.  Even the pyroxenes,
such as diopside, which generally do not show the prominent prismatic mor-
phology because cleavage along the prism planes is not so perfect as it is
i:i amphiboles, tended to orient themselves on the silver membrane and thus
peak intensities in the XRD patterns did not correspond to published data.
Quartz and feldspars were practically the only mineral species detected that
did not exhibit preferred orientation effects in the XRD data.

     The effects of crystal preferred orientations on diffraction peak in-
tensities are very clearly demonstrated by the XRD data obtained for the
phases analyzed of Sample No.  276-1 (Libby, Grade 2).  The phases analyzed
were hand-picked and were relatively pure phase materials.  Diffraction peak
positions were consistent with the phases identified—tremolite and diopside—
but relative peak intensities were not consistent with the published values.
A careful review of the published crystal plane reflections corresponding to
the peaks that demonstrated the greatest variation from published intensity
values clearly indicated that the peak intensity variations were due to crystal
orientation effects.  That is, peaks showing higher relative intensities com-
pared to published data corresponded to crystal planes that were preferentially
placed in the x-ray path (e.g., the elongated axis of a prism or fiber) while
absent peaks or peaks with low intensities compared to published data corre-
sponded to crystal planes placed essentially out of view of the x-rays (e R
the end-on-view of a prism or fiber).

Individual Sample Results

     The results for individual samples follow.   The order of presentation 
-------
     Much of the detailed data and selected photographs are contained in ap-
pendices.  The appendices appear in this volume and three suppleoentary vol-
uraos
     The presentation for each sample include the sample type, code nuobers
aligned to the sample** and appendices page references, optical microscopy
diacription of the sample, and electron microscopy results.

     The detailed optical microscopy examination results presented here are
primarily those submitted by IITRI.  The ORF optical microscopy examination
provided qualitative information on the presence or absence of visible fibers
and identification of those fibers observed.  The ORF results were in agree-
ment with the more detailed results presented here.

     Sample 270. Libby, Montana1  GrarP, r.rade 1. Composite

          IITRI Code No. 129
          Appendix references
            Electron microscope 1-84-87

     Macroscopically, this sample was composed of 1- to 20-nm chunks of gold
to green micaceous minerals, 1- to 15-mm bundles of white to pale green fibers,
and 1- to 8-mm chunks of nonmicaceous, nonfibrous minerals.  The nonaicaceous
minerals ranged in color from deep green, to pale green, to white to colorless.
Prismatic as well as conchoidally fractured chunks of nonmicaceous minerals
were observed.  Fibrous bundles were sufficiently large and numerous to allow
hand-picking before the density separation was conducted.

     The mineralogical composition of the sample, as detenniqed by polarized
light microscopy analyses of the  density-separated and hand-picked fractions,
is presented in Table 13.  Tremolite-actinolite fibers were identified as sig-
nificant sample components.   No fibrous serpentine minerals were detected
    Photographs,  this volume Appendix E,  pp.  E-2 to E-25.
    IITRI EM,  Appendix I,  pp.  1-1  to 1-121.
    IITRI XRD, Appendix I, pp.  1-122 to 1-160.
    ORF EM,  Appendix II (two volumes) pp.  II-l  to 11-203 and 11-204 to 11-420
    Originally the three fractions of the sample composites were assigned
      unique ID numbers.  For this report the designations  were simplified so
      that portions of the same composite sample had the same ID number fol-
      lowed by a  letter indicating the analyzing laboratory.   Most of the
      computer generated data  in appendices  I and II relate to the original
      ID numbers.
                                                                                         •E
                                                                                         rd
                                                                                         10
                                    38

-------
                   TABLE 13.  COMPOSITION OF SAMPLE 270-1


                                             Estimated mass
                    Mineral phase 	concentration (%)


               Tremolite-actinolite fibers         4-6
               Tremolite-actinolite prisms         1-3
               Sphene                              1-2
               Diopside                            2-5
               Augite                              < l
               Hornblende                          < 1
               Magnetite, hematite                 1-2
               Calcite                             1-3
               Quartz                              3-5
               Biotite                             1-2
               Talc                                < i
               Vermiculite                        72-82
               Other minerals                      1-3
     Tremolite-actinolite was identified as the primary fibrous phase present
in the sample.  Fiber color, refractive indices, and extinction angles were
all consistent with a tremolite-actinolite amphibole.  Both colorless (white,
macroscopically) and green fiber bundles were evident; the green-colored fiber
bundles were the more abundant.

     The fibrous phase of this sample was not as well-formed as it was in the
other bulk samples analyzed from Libby.  That is, fiber bundles contained
higher proportions of materials  that would be more correctly classified as
prismatic rather than fibrous, than did other samples from Libby.  Particles
that could readily be classified as fibers tended to be much shorter in this
sample compared to other samples analyzed from Libby.  An unusual morphological
particle type was a significant  component of the fibrous phase of this sample,
and was noted as only a trace component of the tremolite-actinolite phase in
other samples.  The particle type was composed of lamellated tremolite-
actinolite prisms, intergrown at angles as great as 60 degrees to each other.
In other samples, particles composed of the lamellated prisms were composed of
entirely parallel crystals.  It  would appear that the nonparallel intergrown
prisms represent an intermediate metamorphic state, between prismatic and fi-
brous tremolite-actinolite.

     Other mineral types such as diopside, hornblende, sphene, calcite, quartz,
and even the vermiculite tended  to mimic the nonparallel intergrown prism mor-
phology of the tremolite-actinolite, rather than the truly fibrous morphology.

     The degree of intergrowth of amphibole and pyroxene mineral phases with
the vermiculite appeared to be greater in this sample compared to other Libby
samples.  That is, a higher proportion of the vermiculite plates in this sam-
ple contained other mineral phases sandwiched between layers, than other Libby
                                                                                        •e
                                                                                        rd
                                    39

-------
                                                                                         rd
                                                                                         10
samples did.  A higher proportion of the stacked vermiculite plates also ap-             »
peared to be weathered in this sample compared to other samples.  A summary
of the EM results for this sample appears in Table 14.

                    TUU 14. KIWI of IUCTM HionKorr qyATi n» utnt HUT, am. out i               _

             nu, ,-...,..1.. 'ii'""" -  nu, ,-,„""
                                                                  <„.)    tw.t
HQ-t tifclut
*< )!.*
0.9
*.*-ii.l
1.J4-I1.1 0.9
19 M 1.3
l.J • I0"' 1
44 4 ^
r* r
o c
     Sample 276, Libby, Montana, Grace, Grade 2, Composite

          IITRI Code No. 128, ORF No.
          Appendix references
            Photographs E-14,15; XRD 1-157-160
            Electron microscope 1-88-91

     The sample was composed of 1- to  12-mm flakes of  gold  to  deep green mica-
ceous flakes.  White to gray to green  fiber bundles  ranging in diameter from
1 to 5 mm and in lengths from 2 to 15  mm were relatively  abundant.   Other con-
stituents observed macroscopically were glassy, light  to  dark  green mineral
chunks; milky, pale green chunks; and  colorless to milky  white chunks.

     The abundance and large grain sizes of the fibrous bundles allowed for
easy hand-separation of fibers for gravimetric determinations.

     The mineralogical composition of  the sample, as determined by polarized
light microscopy analyses of the various hand-picked and  density-separated
fractions, is listed in Table 15.  The hand-picked fibrous  material was readily
recognized as the tremolite-actinolite amphibole.  No  serpentine fibrous mate-
rial was detected.

-------
                                                                                        rd
                                                                                        10
                                                                                        X
                   TABLE 15.   COMPOSITION OF SAMPLE 276-1
                                             Estimated mass
                    Mineral phase           concentration (%)
               Tremolite-actinolite fibers          4-7
               Tremolite-actinolite prisms          3-5
               Sphene                              < 1
               Diopside                            4-7
               Augite                              1-2
               Hornblende                          < 1
               Magnetite, hematite                 1-2
               Calcite                             1-2
               Quartz                              3-5
               Biotite                             2-4
               Talc                                < 1
               Vermiculite                        66-72
               Other minerals                      1-4
     Tremolite-actinolite was found to be the primary .constituent of the fi-
brous phase of this sample.  Although fiber bundles were up to 15 mm in length,
no single fibers were found anywhere near this length.  Rather, the fiber bun-
dles were composed of short fibers intergrown at slight angles to each other.
All fiber bundles contained both the truly fibrous material as well as the
more bulky, lamellated prisms.  Inclusions such as diopside, hornblende, and
calcite within fiber bundles tended to adopt a fibrous morphology.

     Optical properties of the tremolite-actinolite fibers again included in-
clined extinction angles and refractive indices slightly greater than the
truly prismatic tremolite-actinolite fragments.  Most of the fiber bundles ex-
hibited a slightly greenish color when mounted in immersion oil.  The fibers
were also pleochroic.

     The fiber bundles also probably contained some traces of anthophyllite;
and talc was detected microscopically within several fiber bundles.

     There was an unusual fibrous phase found in the 2.76 sink fraction that
could not be identified.  The fibers had refractive indices higher than the
tremolite-actinolite fiber bundles and were a deep blue-green color.  The
strong coloration resulted in anomalous interference colors similar to those
seen for glaucophane-riebeckite.  This component was less than 0.1% of the
total sample; therefore insufficient material was available for additional
characterization studies.  A summary of the EM results for this sample ap-
pears in Table 16.
                                    41

-------
	 .


«l Ca«M<«act
1*J^1« fWt« lot«r**t


r*«tik

L*4 •«•» to. •!
r«tl«a f i»*r» Ftfc»i
P») «M*tt4 irn
                                                                                         rt)
                                                                                         10
                                                                                         M
  l lirillalrt    J).^                    41. 1     1)    I.)
           Jl.l           0.4               It    1.1
                                 00
     Sample 259, Libby, Montana, Grace, Grade 3, Composite

          IITRI Code No. 122, ORF No. 261
          Appendix references
            Photographs E-2-4, XRD 1-123-125
            Electron microscope 1-14-25, 11-20-43

     Microscopically, the sample was composed of large  (1 to 7 am)  gold  to
black micaceous flakes; dark green, glassy fragments; white to pale green
flexible fiber bundles up to 8 mm in length; and at least three other  color-
less to pale green mineral phases.

     The mineralogical composition of the sample, as determined in  the PLM
analysis of the three density-separated fractions, is listed in Table  17.
Amphibole (tremolite-actinolite) asbestos fibers were found in rather  signifi-
cant concentrations.  No serpentine minerals were detected, however.


                   TABLE 17.  COMPOSITION OF SAMPLE 259-1
                                             Estimated mass
                    Mineral phase            concentration (%)
               Tremolite-actinolite  fibers          <  1
               Tremolite-actinolite  prisms          2-4
               Sphene                               1-3
               Diopside                             3-7
               Augite                               2-3
               Magnetite, hematite                  <  1
               Calcite                              2-5
               Quartz                               2-5
               Biotite                             10-15
               Vermiculite                         65-72
               Other minerals                       1-3
                                     42

-------
     The tremolite-actinolite occurred almost exclusively in an unquestionably
fibrous crystal habit with very little prismatic tremolite-actinolite present.
The fiber bundles were found to be composed of very fine, teasable, flexible
fibers.  In most of the fiber bundles, the individual fibers were not perfectly
parallel to each other and were not as long as the fiber bundles; numerous
small groups of short fibers stacked at slight angles to each other both ver-
tically and horizontally comprised the "fiber bundle."  Optical properties of
the individual fibers included refractive indices greater than 1.610, extinc-
tion angles greater than 0 degrees, and pale green color with slight pleo-
chroism.

     Other mineral phases (including alteration products) were included in
each fiber bundle.  In some cases, these other mineral phases were pseudo-
morphically fibrous.  Quartz, calcite, titanite, and diopside were all ob-
served in a fibrous habit.  Calcite was the most abundant pseudomorphically
fibirous mineral.  Approximately 10% of the "2.76 sink" fraction was composed
of white fiber bundles, which upon teasing and microscopic examination were
found to be composed of 70 to 80% calcite overgrown on 20 to 30% tremolite-
actinolite fibers.

     The tremolite-actinolite fibers were also observed  to be tightly bound to
venniculite plates and growing in between layers of vermiculite.  A summary of
the EM results for this sample appears in Table  18.
IE
rd
10
X

nt>«r* el ill ItBtlh
(CTTOT KICMUOT HJUITJ rt» Ur»U
•

<.„,. *,
«i-i )
151 Cwtfldvu* 1 fiber t c
« iftttrv.l >1»l»fi.<
. i n.i-4*.T
.a IVI-M.I 0.4
t
«.i.»i i.n
.1 • 1.01
.0 JI.I-^O.^
.1 V*. ••!*.* 0.*
.t
i4-l« 0.111
.0 • 0.11B
••cfntr.llv* fib*
118 '
0.01
» 1
»0 101
11
6.1 • ID*1
IW >
r
t 15
r4 N«in
11. »
II. 1
10
' 1.1
1>.>
14.1
It
< 1.0
LIIIT. CUC1. CUM ]
riWfl If.t.f IkM t.O * 1, !.»„»
»^«lv*lMt !• fltlMtt4 Mil
I.I-I7.I 118
t.l-ll.l 0.4
0-11 1.01 11
I.M
J. 1-10.1 140
>. 1-10.1 0.4
>.1-J1 O.MI IW
o.m


«. «f
to
0
0
)4
]4
0
II
0

;;-,
A
T
C
A
C
A
T
C
A
C
       lltolt (SUO)i C • rhrriollU; i
      Sample 282,  Libby,  Grace,  Grade 4,  Composite

           IITRI Code No.  126,  ORF No.  281
           Appendix references
             Electron microscope 1-92-97, 11-356-375

      Macroscopically, the sample was observed to contain mostly 1- to 4-ran
 goldish-brown vermiculite flakes.  White fiber bundles up to 3 mm in length
 were visible.  Nonmicaceous, nonfibrous  mineral phases were also observed; at
 least three different mineral  phases ranging in color from white to emerald
 green were detected.
                                     A3

-------
                                                                                        rd
                                                                                        10
     The mineralogical composition determined  for this  sample by polarized               x
light, microscopy is listed in Table 19.


                   TABLE 19.   COMPOSITION OF SAMPLE 282-1
                                             Estimated mass
               	Mineral phase	concentration (%)

               Tremolite-actinolite fibers     (0.3)-1
               Tremolite-actinolite prisms         1-3
               Sphene                              < 1
               Diopsidc                            3-7
               Augite                              1-2
               Hornblende                          < 1
               Magnetite, hematite                 1-3
               Calcite                             < 1
               Quartz                              1-3
               Biotite                             1-3
               Vermiculite                        78-88
               Other minerals                      1-3
     Tremolite-actinolite was again detected as a significant sample component
and was again present in three distinct crystal habits.   The truly prismatic
tremolite-actinolite was most abundant.  Most prismatic fragments had small
bundles of fibers or bundles of the thin, lamellated prisms (that could readily
fracture to produce particles definable as fibers) attached to them.  Practi-
cally all bundles composed primarily of truly fibrous tremolite-actinolite
contained thick, chunky prisms or the lamellated prisms.  All truly fibrous
treraolite-actinolite bundles were composed of intergrown fibers; i.e., no bun-
dles were composed of uniform length, parallel fibers.  Groups of fibers grow-
ing at angles as large as 75 degrees to each other were observed in the same
bundle.  The lamellated pricm bundles, however, did tend to be composed of
crystals growing parallel to each other.  Bundles composed of both the truly
fibrous material and the thicker, lamellated prisms also tended to be composed
of nonparallel crystal bundles.

     The tremolite-actinolite fiber bundles hand-picked from the sample ranged
in color from pure white to deep green.  Less than 10% of the fiber bundles
were the pure white color; most fiber bundles were pale green and had refrac-
tive indices in the middle range reported for the tremolite-ferroactinolite
solid solution mineral series.  Extinction angles for the truly fibrous crys-
tals and crystal bundles were inclined at least 5 degrees.

     No fibrous anthophyllite, prismatic anthophyllite, or talc were detected
in this sample.  However, some hornblende in a morphology that could be clas-
sified as fibrous was detected.  The hornblende bundles containing crystals
                                    44

-------
                                                                                         ro
                                                                                         JO
classifiable as fibers were composed primarily of the thicker, more brittle              QQ
lamellated prisms.

     The 2.76 sink fraction contained a significant fraction of biotite.  The
other major constituents of this fraction were vermiculite flakes intergrown
with tremolite-actinolite, diopside, and iron oxides.

     The 2.76 float fraction was relatively free of pyroxene and amphibole
mineral fragments.  Few flakes of vermiculite intergrown with amphibole min-
eral phases were detected.  A summary of the EM results for this sample ap-
pears in Table 20.
flb*f» «f ill Imiithi flbtri • -••Ur !••• 5.0 *» !• Itflith . . ..
&••»!•
111-0
Ill-l t-fvlUU'l



1.0 0>1.2 O.)40 1 1-0-4
' 0.4 - 0.3*0 • 0 < 0.4
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,.M,^ «.. ... .t
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0
                         1.144       II       4    0.4    0-1.»     0.444
                         0.44ft       •       0   < O.S     -       0.4*4
     Sample 264, Libby, Grace, Grade 5, Composite

           IITRI Code No.  120, ORF No.  263
           Appendix  references
            Photographs E-5, 18-20, XRD 1-126-129
            Electron microscope  1-26-52, 11-44-166

     Macroscopically,  the sample was observed to be a fine,  goldish-brown pow-
der composed  of obviously flake-like and fibrous particles.   The flake-like
particles  were generally  less than  2 mm in diameter.   Fibers up to 3 mm in
length were present.   At  least two  other nonvermiculite,  nonfibrous mineral
phases were observed;  one was green in color, while the other was colorless.

     The mineralogical composition  of  the  sample determined by PLM analysis of
the three  density-separated fractions  is listed in Table 21.

-------
                   TABLE 21.   COMPOSITION OF SAMPLE 264-1

                                            Estimated mass
                  . Mineral phase	concentration  (%)


               Tremolite-actinolite  fibers    .     2-4
               Tremolite-actinolite  prisms         2-5
               Sphene                             1-3
               Diopside                           6-9
               Augite                             1-3
               Hornblende                          <  1
               Magnetite,  hematite                1-3
               Calcite                            1-3
               Quartz                             1-3
               Biotite                            3-7
               Venniculite                        70-74
               Other minerals                     2-4
     Tremolite-actinolite was present in a fibrous morphology.  In this sam-
ple, however, a significant amount of prismatic tremolite-actinolite was also
present.  Both fibers and prisms exhibited inclined extinction.  There ap-
peared to be some fibers close to the tremolite end member of the series, as
refractive indices of some fibers were observed to be at or just sightly below
1.600.

     The tremolite-actinolite fiber bundles occurred as the nonparallel
stranded bundles.  A higher percentage of the fibers and fiber bundles was
found intergrown with vermiculite, biotite, and the other low density minerals
in this sample compared to the larger particle samples.

     Pseudomorphically fibrous quartz, calcite, diopside, and augite phases
were again detected.  A summary of the EM results appears in Table 22.
                                                                                        rd
                                                                                        10
                                                                                        00
                                    46

-------


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  if IITII uiinf the utF
     Sample 267,  Libby,  Grace. Grade 5. 1 Day

          Appendix references
            Photographs  E-14, XRD 1-153-156

     Macroscopically, the sample was composed primarily of fine (0.5 to 3 mm)
goldish-brown micaceous  flakes.  Pale green to white fiber bundles up to 2 ram
in length were visible.   At least two green, nonoicaceous mineral phases and
one colorless, nonmicaceous mineral phase were observed.

     The mineralogical composition of the sample, as determined by polarized
light microscopy analyses of the various density-separated fractions, is listed
in Table 23.  Fibrous amphibole--mostly  tremolite-actinolite, with some inter-
grown anthophyllite--was definitely present.  No serpentine  fibers were de-
tected, however.
                                     47

-------
                                                                                        re
                                                                                        10
                                                                                        00
                  TABLE 23.  COMPOSITION OF SAMPLE 267-1
                                            Estimated mass
                   Mineral phase            concentration  (%)
               Tremolite-actinolite  fibers          2-5
               Tremolite-actinolite  prisms          4-8
               Anthophyllite  (prisms and  fibers)    <  1
               Sphene                              <  1
               Diopside                           10-15
               Augite                              1-3
               Hornblende                          <  1
               Magnetite, hematite                 1-3
               Calcite                             1-2
               Quartz                              1-3
               Biotite                             <  1
               Talc                                1-2
               Vermiculite                        65-70
               Other minerals                      1-3
     The tremolite-actinolite occurred in many different particles but occurred
predominantly as irregularly fractured fragments of solid prisms.  Prismatic
fragments composed of numerous thin, stacked prisms which were capable of
fracturing into elongated, parallel-sided fragments definable as fibers were
observed but represented less than 1% of the total sample.  Truly fibrous bun-
dles composed of very fine, teasable individual fibers, were significant sam-
ple components.  Typically, the fibrous bundles were composed of short fibers
that were not perfectly parallel.  Rarely were fiber bundles composed of indi-
vidual fibers that ran the entire length of the bundle.  Obvious fibers were
also found attached to (i.e., "growing from") chunky, prismatic fragments and
from the lamellated prisms.  Both prismatic and fibrous varieties of treraolite-
actinolite were found bound to and intergrown with vermiculite plates to a
minor extent.

     The extinction angles of both prismatic and fibrous varieties of the
tremolite-actinolite were on the order of 7 to 18 degrees.  Refractive indices
of the prismatic variety tended to be greater than those of the fibrous habit.
Prism colors were mostly green, while fiber bundle colors ranged from color-
less (white) to pale green, depending upon the types and amounts of inclusions
present within the bundles.

     Anthophyllite fibers and prisms were detected.  The fibrous form was found
only intergrown with the tremolite-actinolite fibers.  Free anthophyllite
prisms as well as prisms intergrown with tremolite-actinolite prisms were
present.  Almost all the tremolite-actinolite fiber bundles that contained
anthophyllite  also contained talc.

-------
                                                                                         re
                                                                                         rfl
                                                                                         .10
     Unlike the 264-1 composited grade 5 sample from Libby,  this uncomposited            <#
sample did not appear to contain other mineral phases in pseudomorphically fi-
broun habits.  None of the fibrous calcite detected in the 264-1 sample was
found in this sample.

     Most of the nonraicaceous contaminant minerals present in this sample were
high density materials and were thus found in the TBE sink fraction.  The 2.76
density fractions were relatively free of nonvermiculite mineral phases, par-
ticularly the 2.76 float fraction.

     Sample 291, Libby. Grace. Head Feed Composite

          IITRI Code No. 130, ORF No. 290
          Appendix references
            Photographs XRD 1-130-134
            Electron microscope 1-2-13, II-1-19

     Macroscopically,  this sample was quite variable  in  color,  particle  mor-
phology,  and  grain size.  The overall color was a  light  brown.   Relatively few
micaceous  flakes were  visible to  the  naked eye; the  largest  flakes  were  less
than  10 mm  in size.  Under the  stereomicroscppe, most of the brownish,  fine
powder  (less  than  1  mm) material  present  was  observed to be  micaceous.   Sev-
eral  large  white to  pale  green  elongated  (and probably fibrous) rock chunks
greater than 20 mm were observed.   Obvious mixed phase grains  (i.e., mineral
phases  partially altered) were  also present  as 1-  to 15-mm  grains.

      Microscopically,  the sample  was observed to be composed primarily of non-
micaceous,  contaminant minerals.   The overall sample composition determined by
microscopical analyes  of  the density-separated fractions is presented in Table
 24.


                    TABLE  24.   COMPOSITION OF SAMPLE 291-1
                                              Estimated mass
                     Mineral phase           concentration (%)
                Tremolite-actinolite fibers        21-26
                Tremolite-actinolite prisms         6-9
                Sphene                              1-3
                Diopside                           24-29
                Augite          :                    2-5
                Hornblende                          < 1
                Magnetite, hematite                 3-5
                Calcite                             3-5
                Quartz                              4-7
                Biotite                             1-2
                Vermiculite                        20-25
                Other minerals                      3-6
                                      49

-------
                                                                                          ft
                                                                                          id
                                                                                          ,10
     Tremolite-actinolite was a major component of  this  sample  and occurred in           oo
both fibrous and prismatic crystal habits.  The fibrous  habit was found as
discrete fiber bundles, fiber bundles intergrown with  prismatic amphibole and
pyroxene mineral phases, and as small fiber bundles protruding  fron vermicu-
lite (or other micaceous mineral) plates.  Fiber bundles were composed mostly
of smaller, shorter irregularly stacked bundles of  fibers,  rather than as
bundles of perfectly parallel, uniform length  fibers.  Optical  properties of
fiber bundles identified as tremolite-actinolite indicated  that a wide range
of chemical compositions was present; i.e.,  some end member tremolite and
ferroactinolite phases as well as the intermediate  actinolite were present.

     The tremolite-actinolite fibrous phase  was  a major  component of each den-
sity fraction because of the multiphase  nature of a large percentage of the
particles  in this sample.  Inclusion of  lower  density phases within each fiber
bundle as  well as attachment of  fiber bundles  to lower density mineral grains
resulted in a lower than normal  bulk density for the tremolite-actinolite.

     Some  unusual fibrous phases were present.  Fiber bundles exhibiting the
anomalous  blue and pink  interference colors  typical of crocidolite  (riebeckite)
asbestos were observed.  The  refractive  indices of these fibers  as well  as
their  inclined extinction angles (and XRD data) ruled out crocidolite  as  the
mineral species.  The  fiber bundles were strongly pleochroic (yellow-green to
blue-green), and  this  undoubtedly caused the anomalous  interference  colors.
Further characterizations by  electron microprobe, micro X-ray  diffraction,  and
electron microscopy must be  performed in order to  fully  identify this  phase.
Possible mineral  Identities  include ferroactinolite,  sodium  tremolite, and
glaucophane.

      Identification  of all  mineral phases present  was impossible.  Hany inter-
mediate, partially  altered  phases were present in  this  sample.   XRD data sug-
gested that antigorite is  present in the low  density  fraction.   A summary of
the EM results  for  this sample appears in Table 25.

  ___ t.iu n. latufi a IUCTK» nicmtopT man n»jwi_iniT. eua,  MAO tup               __
                                                              vo t» i« IMH
                        •*«l*ll«tt !•  lltlMt*4 Mil  to. •(              M»lvtlfM t«  tlttMlrt Mil  ••. •!
                1U CMflfeMt   I flWf   cMiralMIIM  Uteri      nlC««ll«tMI    I IIMr   cMCIIlrillM  IIHrt
                 l»»r>il    4.1. . Hi     In*)    inatlt  MM   llt.r-ll    faUclH         c»»l«4
1-M-l


m-0

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0.111
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                                      50

-------
                                                                                        i
                                                                                        rt
                                                                                        ,10 •
     Sample 294,  Libby.  Grace,  Extractor Waste,  Composite                                oo

          IITRI Code No.  134
          Appendix references
            Photographs  E-15
            Electron microscope 1-98-102

     This sample was quite broad in particle size.   It was composed primarily
of 0.2- to 15-mm gold to brown micaceous flakes.  White fibrous bundles up to
9 mm in length were observed.   The fibrous bundles were sufficiently abundant
and large in size to allow hand-picking after density separations were con-
ducted.  Nonfibrous, nonmicaceous mineral fragments which were mostly green in
color were present in diameters up to 6 mm.

     The mineralogical composition of the sample is listed in Table 26.  Sam-
ple components were identified by polarized light microscopy analyses of the
hand-picked and density-separated fractions.  Fibrous amphibole mineral phases
were detected in the analyses, but no fibrous serpentine mineral phases were
detected.


                   TABLE 26.  COMPOSITION OF SAMPLE 294-1
                                             Estimated mass
               	Mineral phase	concentration (%)


               Tremolite-actinolite fibers         1-4
               Tremolite-actinolite prisms         1-3
               Sphene                              1-2
               Diopside                            3-7
               Augite                              <  1
               Hornblende                          <  1
               Magnetite, hematite                 1-2
               Calcite                             1-3
               Quartz                              4-10
               Biotite                             6-9
               Talc                                <  1
               Vermiculite                        68-76
               Other minerals                      1-3
                                     51

-------
                                                                                          re
                                                                                          in)
                                                                                          .10
     The tremolite-actinolite occurred  primarily as  fibrous crystal bundles              oo
and crystal bundles containing both  fibrous  and prismatic materials.  Coarse
crystals composed only of bulky, prismatic materials were rare.  Tremolite-
actinolite fragments composed only of elongated, narrow,  thin, lamellated
prismatic crystals were also rare but were not as rare as the chunky prismatic
crystals.  Both prismatic crystal morphologies were  observed mostly in con-
junction with the fibrous morphology; that  is, most  of the tremolite-actinolite
mineral fragments that contained prismatic material  also contained at least
25% truly fibrous material.  Fibrous crystal-bundles containing mostly fibrous
crystals were again observed to contain small bundles of short fibers that
were stacked at slight angles to each other both longitudinally and laterally.
Single fibers that ran the  entire  length of the fiber bundle were  rarely seen
and were only observed in rock  fragments that contained at least 35% prismatic
materials.  The fibers grew parallel to and on top of the prismatic material.

     Refractive indices of  the  fibrous  tremolite-actinolite tended to be
greater than those of  the prismatic  tremolite-actinolite crystals.  Practically
all fiber bundles exhibited a green  coloration and pleochroism in  plane  polar-
ized light.  Prismatic crystals tended  to be more strongly colored than  the
fibrous crystals.  Prismatic  crystals also tended to be more  blue-green  than
green.  Extinction angles of  both the prismatic and  fibrous crystal habits
were greater than zero.

     Intergrowth of  tremolite-actinolite and pyroxene minerals with vermicu-
lite was greater in  this  Libby  sample than it was in most  of  the  other Libby
samples  included in  this  group  of 10 lesser priority vermiculite  samples.
This is  reflected by the  relatively high weight percentage of the 2.76 sink
fraction.

     Fibrous phases  in addition to  tremolite-actinolite  were  detected.   Some
pseudoraorphically  fibrous calcite was  found  intergrown  in tremolite-actinolite
fiber  bundles.   Pseudomorphically fibrous diopside  and  (probable) hornblende
were also  detected.   Traces of fibrous  anthophyllite intergrown  with talc
within fibrous tremolite-actinolite bundles  were  also observed.   There were
two additional fibrous phases present  that  could  not be  identified because
they were  present  in such low concentrations and could  not be isolated  for
 further studies.   One fibrous type  exhibited the anomalous interference colors
and higher refractive indices associated with the glaucophane-riebeckite series
 amphiboles.  The other fibrous phase exhibited the  lower refractive indices
 and anomalous interference colors this analyst has  observed in chrysotile sam-
 ples containing biotite and vermiculite.  A summary of the EM results for this
 sample appears in Table 27.
                    ruu ;r sotuiT or menu* Hictojwrr JUUITI ft* auffti UMT. c**ci. tmucro* .
                      fl»tr» •( .It l
            Flfcx t.xii«nt nt i»n [II
    1i\ CMlU#*t»   I llWc   run
fteia   tattrvil    d«lftt«4
                                         .
                                 iaintiwi  tiWfi      *M CMflfeMi   I lltaf   CMCnlfitiM  fltori  ritor
                                 (ffmt    CMIIH  NMi    uicrol    tfturlttf     fn>>    CMal»4  lr»*
 111-1 til. II. I. <   JVO                    >IO      II   II. •
            • M            6.1              101   JS.S
            0.)                  ).» i 10''     1
  A " •WMtali (SAID): C * rhrTiitltlt ••« T •
                                      52

-------
                                                                                        re
                                                                                        ird
                                                                                        ,10
     Sample 297 Libby.  Grace.  Baghouse.  Mill  Dust.  Composite                             w

          IITRI Code No.  136,  ORF No.  296
          Appendix references
            Photographs E-17
            Electron microscope 1-103-108,  11-376-388

     The sample was a brownish-green,  very fine powdered mineral dust.   Obvi-
ously micaceous flakes as large as 4 mm in diameter were observed.   Obivously
fibrous crystals up to 2 ran in length were also detected.

     Density separations in heavy liquids did not result in clean separations
of the various mineral phases.  Fine particle sizes resulted in temperature-
induced turbulent motion of particles rather than strict density settling.
The particles were also extremely agglomerated and thus behaved with the com-
posite densities of the component particles.

     The mineralogical composition of the sample, as determined by the polar-
ized light microscopy analyses of the various density-separated fractions, is
presented in Table 28.


                   TABLE 28.  COMPOSITION OF SAMPLE 297-1
                                             Estimated mass
                    Mineral phase	concentration  (%)


               Tremolite-actinolite fibers         8-12
               Tremolite-actinolite prisms         2-6
               Sphene                              1-3
               Diopside                            3-6
               Augite                              2-5
               Hornblende                      .    <  1
               Magnetite,  hematite                 1-3
               Calcite                             1-3
               Quartz                              2-5
               Biotite                             1-3
               Talc                                <  1
               Venniculite                        55-61
               Other minerals                      2-5
      Tremolite-actinolite was a major sample component.   Bundles composed of
 truly fibrous crystals as well as lamellated prisms and  chunky prismatic frag-
 ments of tremolite-actinolite were detected.  Single crystals of tremolite-
 actinolite in morphologies classifiable as fibers were not unexpectedly abun-
 dant, as the sample obviously was fine particle material produced from frac-
 ture and abrasion of larger mineral grains.  Both the truly fibrous bundles
                                     53

-------
and latnellated prism types of tremolite-actin«lite would be expected to give
rise to single crystals morphologically definable as fibers.  Again, the dis-
tinction between fiber-like amphibole crystals produced from particles macro-
scopically definable as fibrous and fiber-like crystals produced from nineral
grains composed of thin, narrow, lamellated prisms, may be immaterial.  It was
certainly not possible to define the origins of all the fiber-like tremolite-
actinolite single crystals present in the sample.

     Anthophyllite was again detected as a very trace (< 0.1%) sample compo-
nent.  Fibrous hornblende and the unidentified fibrous blue-green amphibole
were also detected again.

     Traces of a mineral with morphological and optical properties similar to
nonfibrous serpentine were detected in the 2.76 float fraction.  Concentration
of this possible serpentine was estimated to be well below 0.1% of the  sample.
The low concentration precluded further isolation for verification of  the pro-
posed identity.  A summary of the EH results for this sample appears  in Table
29.
                                                                                       re
                                                                                       «j
                                                                                       10
                                                                                       oo

rcHri it iii imiti r
tor* iriitir tkM i.o im !• Itvclk
"TlUc iMtfiiiiim no- iiMff/u tim STiTvivin ii-.im[ii»4—
^Ti»in"" tllMt* Mil U. •! t«l«i«i'« bllMlM MM to. .1
m CM|I0 100 *]•
< 1.1
»>•! tlf.H.IM III

,U 1.10 4. WO « »» W-JI I.JO ».«>• «1
1.10 • 0 < 1.1
I). 00* 1M Ul
I.I III tot
0
1.10 • »
It. 000 10
I.I '1

I < > ttltltolt IIAIDIi C • TkrTMtllll >M T • Ulll.
     Sample 288,  Libby,  Grace,  Screening Plant Dust,  Composite

          IITRI  Code No.  135,  ORF No.  287
          Appendix references
            Photographs  E-16
            Electron microscope 1-108-113, 11-389-402

     Macroscopically, the sample was observed to be a very fine, pale green
powder.   Obvious micaceous flakes up to 2 mm in diameter were present.  From
the bulk density of the  sample, it appeared that micaceous type minerals were
the primary sample components.

     Density separations produced a deeper green, powdery fraction (sinks in
tetrabromoethane) , a brownish-green fraction with some micaceous flakes (sinks
in 2.76 density liquid), and a gold-colored fraction obviously composed pri-
marily of micaceous flakes (2.76 floats fraction).  The mineralogical composi-
tion of the sample, as determined by polarized light microscopy analyses of
the three density-separated fractions, is presented in Table 30.  Separations
of the density fractions were not very clean, in part due to the very small
grain sizes, but mostly due to the intergrowth of high density phases with low
density phases.

-------
                                                                                       re
                                                                                       rt
                                                                                       .10
                                                                                       00
                  TABLE 30.  COMPOSITION OF SAMPLE 288-1
                                            Estimated mass
                   Mineral phase	concentration (%)


              Tremolite-actinolite fibers         2-5
              Tremolite-actinolite prisms         1-4
              Sphene                              <  1
              Diopside                            3-6
              Augite                              1-2
              Hornblende                          <  1
              Magnetite,  hematite                 1-3
              Calcite                             1-3
              Quartz                              4-7
              Biotite                             1-3
              Talc                               <  1
              Vermiculite                        68-78
              Other minerals                     1-4
     Identification of mineral phases was somewhat hindered by the relatively
small particle sizes of the fractured mineral fragments.  Numerous shards of
vermiculite were present and could easily be mistaken for fibrous mineral types
on morphology only.  The vermiculite shards could easily be distinguished from
the fibrous amphiboles on the basis of refractive index, however.

     Although the mineral fragments in the sample were quite abraded and frac-
tured, three distinctly different morphologies of the tremolite-actinolite
mineral phase were observed.  The chunky, prismatic crystals that would not
fracture to produce fragments definable as fibers were the least abundant
tremolite-actinolite phase present.  Fragments composed of elongated, narrow,
thin, lamellated tremolite-actinolite prisms were as abundant as the bundles
of nonparallel intergrown, truly fibrous tremolite-actinolite crystals.  Mor-
phologies of the very small  (less than 10 \m wide) single tremolite-actinolite
crystals that could be classified as fibers on the basis of aspect ratios sug-
gested that equal  proportions of the larger lamellated prisms and true fiber
bundles had been abraded to  produce the single crystals.  That is, many of the
"fiber-like" single crystals were more platey than true fibers would be ex-
pected to be.  However, at this small particle size, the origins of particles
classifiable as  fibers--either from lamellated prisms or true fiber bundles--
are  only speculation  and may well be immaterial.

      In addition to the tremolite-actinolite  fibrous amphibole,  fibrous antho-
phyllite was  detected by its parallel extinction  angles and different refrac-
tive indices.  Fibrous  anthophyllite was well below 0.1% of the  sample mass;
 it was most  frequently  found in association with  talc.
                                     55

-------
                                                                                      ft
                                                                                      ird
^,,u°ther fibr,ous Phases present included a  morphology of hornblende that              I1°
couia DC  considered fibrous, and na»nrinmnmh<<»aii..  r^i...... ...._*._	i __i_^_           oo
 could h   r«           v
 The unfL«?°« Si™ Kiflbr°U8> and P8cud°n,orphically  fibroui quartz and calcite.
 If«n?i  I   ftable blue-green amphibole with  the anouloue interference colors
 similar  to glaucophane-riebeckite series amphiboles was again detected.

 in.*..1?6  2>?6 f.°at fraction contained  a mineral phase with optical and morpho-
 logical properties consistent with nonfibrous serpentine.  Insufficient numbers
 of  P«ticle8 were available for further identification studies.  A suamary of
 the EM results for this sample appears  in Table 31.
                 _r«»mii Pftxn or mem niacitorr m,
    ....     -  -sr  TS- =5* H  .„ -as-


lll-l b(tlliu<

»0 IW-MO

1,100
1. 100

'•" >."5 III 10* 11. IW 1 II
I.M - 9 < 1 t . | {J
».( tl.OOO t| |,fM
0


• c
II t

     Sample 430. Enoree.  South Carolina. Grace, Grade 3. Composite

          IITRI Code No.  121, ORF No. 429
          Appendix references
            Photographs E-7-8, XRD 1-135-138
            Electron microscope 1-60-65
hroUnh->  the  Sample was Ob8crved to contain 1- to 5-mm black  to
brownish-gold nucaceous  flakes, and 1- to 3-mm fragments of nonmicaceous min-
erals.   The nonmcaceous minerals were white, pale green,  or reddish-brown in

                   V       "'                            '"
     The composition of this sample as determined by PLM analyses  of  the
density-separated  fractions is listed in Table 32.       anaiyBes  01  tne
                                   56

-------
                                                                                         TE
                                                                                         ird
                                                                                         no
                    TABLE 32.   COMPOSITION OF SAMPLE 430-1                                «o
                                              Estimated  mass
                     Mineral phase	concentration  (?

                Anthophyllite                       <  j
                Tremolite-actinolite                 2-4
                Augite                              <  j
                Hornblende                           j_2
                Apatite                              j_2
                Magnetite,  hematite                  1-2
                Calcite                              <  j
                Quartz,  feldspars                    4-5
                Talc                                 j.j
                Vermiculite                       80-90
                Other minerals                       1-2
     As  is  evident  from Table 32, the sample was composed primarily of vermic-
 uUte    Relatively  little contaminant, nonvermiculit? mineral matter was
 present.


 Th.  Botht!:emolite~?ctinolite and anthophyllite amphiboles were detected.
 The tremolite-actinolite occurred almost exclusively in a very bulky  wis-
 fr ctu;e0rPfrom°tr  However' '-"el-gated, parallel-sided £rUc& cou d
 fracture from these prisms to yield particles classifiable as "fibers "  So
 few large particles of anthophyllite were observed that it is impossible to
 confidently state whether or not truly fibrous anthophyllite was present
 Certainly, elongated fiber-like particles of anthophyllite were observed.

     The 2.76 float density-separated fraction contained some unusual, not
     iv character,^!,. ..^lti.  irregular, light green particles closed
                             rather similar to serpentine minerals WP™ pre8-
258        '''"'"such-  A iamtry °f th<
           f|t.|
           :::   '•"'••     •••       ,.;...    »    -           ...        ••"     ;    •
          -t!   °"-"     S:£      V       I   :::}     :      -      :      j    j
.»-.«.,.„.,-    ,.,           .         ,,     u                                •
                                       «    ,.,           ...        >••     i    .
tJO-O Uflll.lH    1.1    J.J.4     0 «fll     '  I       ...                           «    C
                        •:-      •       S   :::5     :      2:2!      :      •    •
                                    57

-------
                                                                                   re
                                                                                   "a
Sample 433, Enoree. South Carolina, GracRr    4  Comosite                      ho
                                    —^————————•	                      100
     IITRI Code No.  127,  ORF No.  432
     Appendix references
       Electron microscope 1-114-119,  11-403-420
             TABLE 34.  COMPOSITION OF SAMPLE 433-1


                                       Estimated mass
         	"meral phase	concentration  (


         Fibrous mixed amphibole             < j
         Anthophyllite-prismatic             1-3
         Tremolite-actinolite                1-4
         Sphene, ilmenite                    < j
         Augite                              < j
         Apatite                             j_.j
         Hornblende                          2-5
         Magnetite, hematite                 1-2
         Rhodonite, pyrolucite               < i
         Calcite                             < j
         Quartz, feldspars                   3.3
         Talc                                1-3
         Vermiculite                         7c 01
         -.,     .       •                     fJOi
         Other  minerals                       2-5

                             58

-------
     Tremolite-actinolite prisms were generally pale green and pleochroic, and
exhibited inclined extinction.   The anthophyllite was colorles (in transmitted
light), had refractive indices  lower than the tremolite-actinolite, and exhib-
ited parallel extinction.  Tremolite-actinolite was occasionally found inter-
grown with hornblende.  The anthophyllite and tremolite-actinolite prisms were
never found intergrown with each other in the same mineral fragment in this
sample.

     The relatively high proportion of the 2.76 sink density-separated frac-
tion reflects the degree of intergrowth of the amphibole and pyroxene mineral
phases with the venniculite.  In general, the vermiculite plates of this  sam-
ple were more irregular, strained, and intergrown with other mineral phases
than were the venniculite plates of most of the Libby, Montana, samples.  At
least two other micaceous mineral phases that could not be identified were
present in addition to the vermiculite.  As these phases were micaceous,  they
were included in the mass accounting for venniculite.  A summary of the EM
results for this sample  appears in Table 35.
                                                                                        rt
                                                                                        ird
                                                                                        no

1--I— fl
FlWt t»,..lr.H~ [I
iMflt I*J4« I4t«ml
411-1 1.4
4.1

411-0 1.1 0.1-1.)
< 0.1
411-1 llf.lllKl 1.1
1.1

411-0 t.t.ll.1.4 1.1 0.1-4.1
< 0.1
k»fl 4f 41 titilhB
'LI..ii!.'L
I llto
ttl«ll<

O.I

0.1U
0.24*

0.4

0.144
0.141
tlllMU4 MM •». •(
"•" '"""4
I.I II
4
0 0
U II
0
1.4 1
II
0
: 10
0
lit... .r
IVtitm i1' » JBJIUH 	
fiHf t»*cmt4ii«« I1U .. "f"'fj —
C4MM4r4tlM
•^ilnlffBI t* C4UM144 M4I ••.
til CMrifttae* 1 tlfe*r c«M4«lr4tlM (Ito
«... i.<.r.il
O.J
t.l

0.1 IHJ.I
« 0.1
1.4
0.4

< 0.)
< 1.)
••UCIH (*f41) C*M
>.S
• .1

«.iu n
0.14*
0.44
O.I

0.1M
0.144
1
44 «r»«
A
7
C
«
C
A
T
C
A
C
I  4 • M»hlk*lt IIAUll C • (lrrl«lllll *M 7 • ttl4l.


      Sample 427,  Enoree,  South Carolina,  Grace, Grade 5, Composite

           IITRI Code No.  119, ORF No.  426
           Appendix references
             Photographs E-8-10, 21-23, XRD 1-139-142
             Electron microscope 1-66-78,  11-204-334

      The sample was a goldish-brown powder composed of less than 2-mm flake-
 like particles.  No obviously fibrous phases were detected in the macroscopic
 examination.   Submillimeter grains of nonmicaceous gold, green, colorless, and
 white minerals were observed in the stereomicroscopic examination.

      The rnineralogical composition of the sample determined by PLM analyses of
 the density-separated fractions is listed in Table 36.
                                      59

-------
                                                                                        re
                                                                                        irfl
                                                                                        110
                  TABLE 36.  COMPOSITION OF SAMPLE 427-1                                m
                                            Estimated mass
                   Mineral phase	concentration  (%)


               Fibrous  mixed aopbibole              <  1
               Anthophyllite                        4-6
               Tremolite-actinolite                 2-4
               Sphene,  ilmenite                     1-3
               Hornblende                           2-5
               Apatite                              1-2
               Magnetite,  hematite                  <  1
               Rhodonite,  pyrolucite                1-2
               Calcite                              <  1
               Quartz,  feldspars                    3-6
               Talc                                1-3
               Vermiculite                        72-78
               Other  minerals                       1-3
     Definitely fibrous mineral phases were detected in the tetrabromoethane
sinks fraction.  However, the fibers were well below 10% of the TBS fraction
and thus were less than 1% of the total sample.  Analysis of selectively re-
moved fibers indicated that both anthophyllite and tremolite-actinolite were
present within the fiber bundles.  The anthophyllite was identified by its
parallel extinction and its slightly lower refractive indices compared to the
tremolite-actinolite.

     The anthophyllite and tremolite-actinolite occurred primarily in very
clearly prismatic crystal habits.  However, grinding of the prisms did produce
parallel-sided, elongated particles which could be classified as fibers.

     Talc was  found both as free plates and incorporated within the fiber bun-
dles.  The talc incorporated within the fiber bundles tended to be fibrous  in
morphology.

     Some pseudomorphically fibrous mineral phases were found in this sample.
Some of the  sphene  (titanitel and fluorapatite were present as fractured frag-
ments morphologically  characterizable as fibrous.  A summary of the EM re-
sults for this sample  appears in Table 37.
                                     60

-------
                      r»l«lt«l u mint* mil  It. .f
             Ml CMfl«nc>   i liter   mnMMilM  fltaro
               1.1.ml     4itKlt4     (m)    nmlH
 I (iMr
OlUtul
titMlM OM4 ••. «f
r»n>uitl« lltari  n«,,
  (»•»    natM Irx
417-1


427-0

427-1 
-------
                                                              MIDWEST RESEARCH INSTITUTE
                                                                         425 Volfcer Boulevard

                                                                      Kansas City. Missouri 04110
                                                                       Telephone (816) 753-7600
September 30, 1982
Dr. E. T. Chatfield
Ontario Research  Foundation
Sheridan  Park  Research Community
Mississauga, Ontario, Canada
L5K 1B3

Dear  Dr.  Chatfield:
 Asbestos Contamination."

 I wish to thank you  for your contribution to  this  task and in the prepara-
 tion of the report.

 Sincerely,
 Gaylord  R.  Atkinson
 Task  Leader
 Approved:
   5hn E. Going    /
  Task Manager

  GRA:JEG:bm

  End .

-------
                                                              MIDWEST RESEARCH INSTITUTE
                                                                         425 Volker Boultvaro
                                                                      Kansas City, MlMOurl 64110
                                                                       Telephone (816) 753-7600
September 30, 1982
Mr. David R. Jones
I IT Research Institute
10 W. 35th Street
Chicago, IL  60616

Dear Mr. Jones:

Enclosed is one copy of  the Vermiculite final report,  "Collection, Analy-
sis and Characterization of Vermiculite Samples  for Fiber  Content and
Asbestos Contamination."

I wish  to thank you for  your contribution to this  task and in the prepara-
tion of the report.

Sincerely,
Gaylord  R.  Atkinson
Task Leader
 John E.,Going
 Task Manager

 GRA:JEr,:bm

 End.

-------
                   TABU: 38.   COMPOSITION OF SAMPLE 436-1
                    Mineral phase
 Estimated mass
concentration (
               Fibrous mixed amphiboles
               Anthophyllite-prismatic
               Tremolite-actinolite
               Sphene
               Hornblende
               Apatite
               Magnetite, hematite
               Rhodonite, pyrolucite
               Calcite
               Quartz, feldspars
               Talc
               Vermiculite
               Other minerals
       < 1
       1-3
       6-9
       2-4
      11-15
       2-4
       1-3
       1-2
       1-2
      23-28
       3-5
      32-40
       1-3
     Fibrous amphibole mineral phases were detected, mostly in the tetrabromo-
ethane sinks fraction, but were less than 1% of the total sample.  Both antho-
phyllite and tremolite-actinolite fibrous amphibole phases were detected.  In
addition, it is likely i:hat fibrous hornblende was also incorporated within
the fiber bundles.

     The three major amphibole types present, anthophyllite, tremolite-
actinolite, and hornblende, occurred predominantly as prisms.  Fracture of
hornblende prisms to yield particles classifiable as fibers is unlikely.
However, the prisms of anthophyllite and tremolite-actinolite were obviously
layered and cleavable to particles definable as fibers.

     Talc was again rather abundant and was also found as fracture fragments
that might be classified as fibers.

     The milky green, rough textured, irregular mineral grains were isolated
from the TBS fraction an.d analyzed separately.  Morphologies of the crushed
fragments produced in grinding ranged from irregular to elongated prisms.
Color and extinction characteristics (as observed on paralled-sided fragments)
were consistent with tremolite-actinolite, but refractive indices were slightly
lower than the indices of the glassy, obviously prismatic fragments of
tremolite-actinolite observed in the sample.  X-ray diffraction studies of
this phase indicated this material was a sodium tremol'ite.  A summary of the
EM results for this sample appears in Table 39.
                                    62

-------
             T>IU n. B»a>»T » ivunef IIIOMCTT tuctTi PM uiru DCTC. torn oaeum.
                                                   tiwf« irm«c "" 'Q "• '• '«"'»
                      •ttr.ilrat i. UtUtlM mi  •>. •(              ««.ITIUU u UllliM «o  to. •(
              Ht CnfKMcf   I liter   CMtnlnllo  llMn      nl CMfldran   I lltot   c«*cwnll»  tlWti
               liuml    )    1«>IW  Rtn   I turn I
           O.J                      o.tl    II    O.I        '              •.»     )    t
           <•>    ».)•). I     o.o)              n    o.i            o.i               t    r
                                         0                                  0    C

          "     '•>•>•     0-lM      II      f>    1.0    O.l-l.l    0.1M      II       t    >
           »•!     0-0.1     O.IW      < I       I    0.1     0-4.1    O.IH      < I       1C

           |.|                      o.ll     1                   '               0    A
           > '            (••»              u    o,»            o.t               i    r
                                         0                                  0    C
       IUD)| C • ctryMtllii M t • I. 111.
     Sample  439,  Enoree, South  Carolina/ Grade 3,  Commercially Exfoliated

           IITRI Code No. 133, ORF No.
           Appendix references
             Electron microscope 1-120-121

     The  sample was typical  in  appearance of expanded vermiculite  used as
packing material  or soil conditioning material.   Individual particles were
obviously composed of multiple, stacked vermiculite plates.  Colors  of the
stacks ranged from white to  tan to brown to light green.  Diameters  of the
plates ranged from 1 to 5 mm.   Lengths of the expanded stacked plates were
quite variable and ranged up to 15 mm.  Non nonmicaceous mineral phases were
detected  in  the gross, stereomicroscopic inspection of the sample.

     Density separations did not yield much higher density (greater  than 2.76)
material.  Table 40 lists the mineralogical composition of the sample deter-
mined by  the polarized light microscopy analyses.


                    TABLE 40.  COMPOSITION OF SAMPLE 439-1
                                               Estimated mass
                     Mineral  phase            concentration (%)
                Fibrous mixed  amphibole              <
                Anthophyllite-prismatic              <
                Tremolite-actinolite                 <
                Sphene                                <
                Augite                                <
                Apatite                               1-3
                Hornblende                            <  i
                Magnetite, hematite                  1-2
                Rhodonite, pyrolucite                <  1
                Calcite                               <  i
                Quartz                                1-3
                Talc                                  1-2
                Vermiculite                          85-95
                Other minerals                       1-3
                                      63

-------
     Fluorapatite was the primary  nonmicaceous mineral constituent of both the
tetrabromoethane and 2.76 sinks  density-separated fractions.  Apatite crystals
were significantly larger in  size  and more abundant than any other nonmicaceous
mineral phase detected.

     Particles classifiable as fibers on a morphological basis, upon high mag-
nification inspection, were found  to be mostly vermiculite shards and scrolls.
Refractive indices were a major  characteristic observed to distinguish vermic-
ulite "fibers" from amphibole fibers since vermiculite refractive indices are
significantly lower than tremolite-actinolite and anthophyllite refractive
indices.

     Tremolite-actinolite and anthophyllite were present as coarsely prismatic
material and as fine fractured particles classifiable as fibers.  The pris-
matic crystals each comprised less than 10% of each sink fraction and were
thus each less than 0.1% of the  total sample.  The fiber-like crystals were
present at a count rato of one per 1,000 particles; on a mass basis, therefore,
their concentrations would have  to be in the parts per million range.  A  sum-
mary of the EM results  for this  sample appears in Table 41.

           T"H «!• «^m * tmrgJ!lggt<»T Win P* F*H I***. *m cuauu. • tlllMtM XII  N. .1
                               '•Mnlnlio  litori      111 CatI4nci   I fitaf
               m CnllMui   int                     	    	   		_   	
           Hum   tiurval    telMU4     Iffm)    e*Ml*4 n«M   ~uur»l *  teuct«4   '  (ppaf"    ctwtt* i'
    M,lik.l. (UIOI. C '
     Sample 442, Enoree,  South Carolina, Grade 4, Commercially Exfoliated

     This sample was  a  fine-grain, expanded vermiculite.  The expanded,  stacked
vermiculite plates  visible in this sample ranged in diameter from  0.5 to 3 ran.
Lengths of the  stacked  plates ranged from 1 to 5 mm.  Particle colors were
white, tan, brown,  and  greenish brown.  No nonmicaceous mineral phases were
detected in the macroscopic inspection.

     Density  separations  of this sample also produced relatively little  high
density  (greater than 2.76) material.  The mineralogical composition of  the
sample determined  in  the  polarized light microscopy analyses of the  various
density  fractions  is  presented in Table 42.
                                     64

-------
                   TABLE  42.   COMPOSITION OF SAMPLE 442-1

                                            Estimated mass
               	Mineral phase	concentration  (%)


               Fibrous  mixed  amphibole             <  1
               Anthophyllite-prismatic             <  1
               Tremolite-actinolite               0.5-1
               Sphene                              <  1
               Augite                              <  1
               Apatite                             1-2
               Hornblende                         <  1
               Magnetite, hematite                1-2
               Rhodonite, pyrolucite              <  1
               Calcite                             <  1
               Quartz                               1-2
               Talc                               <  1
               Venniculite                        85-95
               Other minerals                      1-2
     Tremolite-actinolite was the primary nonmicaceous mineral type in both
the tetrabrornoethane and 2.76 sinks fractions.   It occurred primarily as
coarse, chunky prisms.   Up to 10% of the tremolite-actinolite occurred as
overall prismatic fragments composed of elongated, thin, narrow lamellated
prisms.  This crystal form undoubtedly produced many of the small, fiber-like-
crystals observed.  The larger anthophyllite fragments present occurred only
as the chunky prisms.

     The very small (less than 10 pm diameter)  amphibole crystals present in
morphologies definable as fibers were both anthophyllite and tremolite-
actinolite.  It was impossible to determine if these fine, fiber-like crystals
were abraded from large bundles of truly fibrous material or were fractured
from the lamellated prisms.  Number concentrations of the fine, fiber-like
amphibole crystals were greater in this sample compared to sample 439-1.
However, mass concentrations must be considered to be again in the parts per
million range.

     Sample 573, Enoree, South Carolina, Patterson, Ungraded, Composite

          IITRI Code 124, ORF No. 572
          Appendix references
            Photographs E-13, 24-25, XRD 1-148-152
            Electron microscope 1-79-83, 11-335-375

     Macroscopically, the sample was observed to have a wide size range and to
be a brownish-gold material with some obviously micaceous flakes.  Brownish-
gold,  nonmicaceous grains ranged up to  10 mm in size, while the micaceous
                                    65

-------
flakes were 7 to 8 an in ••ximua dimension.   Fragments of nonmicaceous min-
erals up to 20 no in diameter were present.   Colors of the nonmicaceous min-
erals were milky white, milky green, and glassy green.  No obviously fibrous
phases were observed in either the unnagnified or stereomicroscopic examina-
tions.

     The composition of the sample, as determined by PLM analyses of the
density-separated fractions, is listed in Table A3.


                   TABLE 43.  COMPOSITION OF SAMPLE 573-1
                                             Estimated mass
               	Mineral phase	concentration (%)


               Fibrous mixed amphiboles            < 1
               Anthophyllite                       4-8
               Tremolite-actinolite                8-12
               Sphene, ilmenite, rutile            1-2
               Hornblende                          1-3
               Apatite                             1-2
               Magnetite, hematite                 1-2
               Rhodonite, pyrolucite               < 1
               Calcite                             < 1
               Quartz, feldspars                  26-32
               Talc                               12-16
               Venniculite                        33-38
               Other minerals                      1-3
     This sample appears to have been exposed to some type of heat treatment.
Glassy agglomerates were observed in the total sample and were, of course,
concentrated  in the 2.76 floats fraction.

     No  obviously  fibrous bundles were observed in the  stereomicroscopic exam-
ination  of  the TBE fraction.  Small, elongated, coarse  fibrous to prismatic
white particles were observed in the TBE fraction; however, they were  in
greater  abundance  in the 2.76 sink  fraction.  In the TBE, this particle type
was  less than 1% of the fraction, while in  the 2.76 sink the prismatic to
coarse fibrous phase represented 10 to 20%  of the fraction mass.  These par-
ticles were generally  not teasable  with a fine needle and thus are not in a
true fibrous  habit.  However, gentle crushing and grinding produced  long, thin
parallel-sided particles which would be classifiable as fibers.

      The TBE fraction  contained numerous pale green, prismatic amphibole min-
eral particles which were determined to be  tremolite-actinolite.  Again, even
 these clearly prismatic particles could be  fractured to yield particles defin-
able as  fibers.  Although the anthophyllite comprised 10 to 20% of this frac-
 tion,  practically  all  of it  also occurred in an obviously prismatic  crystal
                                     66

-------
habit.  While  fracture of the prismatic anthophyllite could yield fragments
classifiable as  fibers, this fracture was not  readily accomplished;  irregular,
jagged fragments tended to be produced.

     The prismatic  to coarse fibrous mineral phases found in abundance  in the
2.76 sink fraction  were isolated and carefully examined.  The particles were
found to be composed almost exclusively of  talc and anthophyllite.   Tremolite-
actinolite was only a trace constituent of  this fraction.  Grinding  of  the
particles resulted  in ready fracture of both the talc and anthophyllite into
long, thin, parallel-sided fragments classifiable as fibers.  Larger fragments
showed splintered ends suggestive of fiber  bundles.

     Unlike the  Grace samples from South Carolina, the Patterson sample con-
tained predominantly rutile rather than sphene titanium phases.  Some of the
rutile was found in elongated, thin crystal habits.  A summary of the EM re-
sults for this sample appears in Table 44.
              T"g **• HWT °f ittgy* "lireyn *W* n» »«n* a**n. *m cuauu. utroai. nameo
           -rre;
                           '""*'"*
                                                    tit*n tT9*\»t i>«< a.o •! i« i«>ttii
                       •^HlVtl*«t 1* t*lt*tlt
               n\ CMM«MC*   I (itor   CMC MI i
                l«uml    4«t*«t*4     (MI
|Wfi jpMtf UM> VO
.UM Ho- fl^Ti/J
    C««c«atr*iT«i
       ntraii
    M^lWUM t» bllMt«4 MM  ••. •(
      I lltar   CMCMtrciia  flWrt
                       •i  flUj
111-1


111-0
*
111-1. llf.lUIX


111-0. tif.ll.t.4

1 0.01 1.1 i !•"•
H
1 1.4 I 10 •
O.t-l.l O.IU 11
O.IU
1.0
O.I |
I.I 1 !• •
0.1-1.0 o.m 4
O.lftl

0.0)

O.I
< 0.)
O.I
O.I

0.1
> < O.I

0.0) |

o-i. i o.iu a ]
0.24* . 0
1 4 1
0-1 ' J
0
o^.t o.m 4 i
0.2U - 0 C
 » • .^tltoli (UO)| C • OfTMIIIil 
-------
      TABLE 45.  RESULTS OF THE PHASE CONTRAST ANALYSIS OF AIR SAMPLES
                   COLLECTED AT THREE VERMICULITE SITES
Sample
Libby, Grace
106 Field blank3
133 Field blank3
131 Front loader
148 Pit haul driver
138 Mine analyst
141 Bottom operator
130 No. 2 operator
139 Dozer operator
101 Shuttle truck
104 Screening plant, DW
111 Screening plant, DW
108 Trailer court
136 No. 5 substation
South Carolina, Grace
312 Field blank3
346 Field blank3
340 Mill monitor
321 Mill lab technician
301 Dragline operator
347 No. 4 bagger
330 No. 3 bagger
328 Mill (ENE) downwind
335 Mill (N) crosswind
307 Mine (N) crosswind
323 Mine (E) downwind
338 Mine (W) upwind
310 Truck driver
300 Screening plant floor
South Carolina, Patterson
505 Field blank3
533 Field blank3
508 Payload operator
520 Plant foreman
542 Bagger/forklift
513 (NE) downwind
506 Control off-site
515 (SE) crosswind
528 (SW) upwind
Sample
vol. (£)

—
-
303
297
294
276
285
270
385
390
368
169
111

—
-
340
478
240
316
285
287
80
291
154
264
257
354

_
-
255
252
249
188
274
299
147
Fibers/cc
ORF

< 0.02
0.03
0.02
< 0.01
1.5
1.2
3.1
0.02
0.1
0.08
0.1
0.03
0.03

< 0.02
< 0.02
0.03
0.07
< 0.01
0.06
0.1
0.05
0.04
< 0.01
0.01
0.03
< 0.01
0.06

< 0.02
< 0.02
< 0.01
0.01
< 0.01
< 0.01
< 0.01
0.01
0.02
IITRI

0.04
0.05
0.04
0.01
1.9
0.4
9.7
0.2
0.2
0.5
0.02
NDB
0.02

0.04
0.02
0.03
°'g
NDB
0.1
0.05
0.04
NDB
0.02
0.02
0.01
0.3
0.14

< 0.01
0.02
0.04
0.3
0.1
NDv
NDb
0.01
NDB
a  Vclues for blanks were calculated assuming a 100-liter sample.

b  ND:  No fibers detected (100 grids).

                                     68

-------
                             REFERENCES

Spumy, K.  R.,  W.  Stober,  H.  Opiela,  and G.  Weiss,  "Size-Selective
  Preparation of Inorganic Fibers  for Biological  Experiments," American
  Industrial Hygiene Association Journal,  40,  20-38 (January 1979).

Chatfield,  E. J.,  and G.  M. Lewis, "Development and Application  of  an
  Analytical Technique for Measurement of Asbestos  Fibers  in Venniculite,"
  In:  Scanning Electron Microscopy/1980/I,  SEM,  Inc.,  AMF O'Hare
  Chicago,  Illinois, p.  329-340, 328.

Trimbrell,  V.,  "The Inhalation of  Fibrous Dusts," Annals of New  York
  Academy of Sciences, 132, 255-273 (1965).

Going, J.,  and J.  Spigarelli, "Environmental Monitoring Near Industrial
  Sites:  Vinylidene Chloride," EPA-560/6-77-026  (1977).

Going, J.,  "Environmental Monitoring Near Industrial Sites:  Acrylamide,"
  EPA-560/6-78-001 (1978).

Going, J.,  P. Kuykendahl, S. Long, J. Onstot, and K. Thomas, "Environmental
  Monitoring Near Industrial Sites:  Acrylonitrile," EPA-560/6-79-003
  (1979).
                                69

-------
                          APPENDIX A


STUDY PROTOCOL FOR THE COLLECTION AND ANALYSIS OF VERMICULITE
   AND RELATED SAMPLES FOR THE EVALUATION OF FIBER CONTENT
             WITH EMPHASIS ON ASBESTIFORM FIBERS

-------
                                   TASK 32
       STUDY PROTOCOL FOR THE COLLECTION AND ANALYSIS OF VERMICULITE
          AND RELATED SAMPLES FOR TriJT EVALUATION OF FIBER CONTEMt
                    WITH EMPHASIS ON ASBESTIFORM FIBERS	


I.  Background

          In December 1978, the venniculite industry submitted information to
the EPA regarding health problems experienced by employees who were processing
asbestos-contaminated venniculite.  The original submission indicated that
bloody pleural effusions had been detected in 4 of 350 employees; symptomatol-
ogy and clinical findings in the employees were similar to those found in in-
dividuals with asbestos-related diseases.  Subsequent follow-up studies by the
Occupational Safety and Health Administration (OSHA) revealed an even higher
prevalence of health problems among the employees.

          Vermiculite is a hydrated magnesium-iron-aluminum silicate  which has
been mined in the United States since 1929.  After mining, vermiculite is pro-
cessed to remove impurities, including asbestiform minerals; however, all con-
taminants are not removed.  Information suggests that the three major domestic
deposits in Montana, South Carolina, and Virginia contain asbestiform minerals.
Some impurities, including asbestos, may remain as a contaminant in processed
vermiculite.

          Although vennicuiite may contain fibrous materials, the health ef-
fects from vermiculite itself are unknown at this time.  A priority review of
asbestos-contaminated vermiculite, completed by the Office of Testing and Eval-
uation in June 1980, suggested that the asbestos in venniculite may be respon-
sible for the reported adverse health effects, and it concluded that certain
information gaps needed to be filled before an in-depth risk assessment on
vermiculite could be initiated.

          Several projects have been initiated to fulfill the information gaps
nnd complete the preregulntory analysis on venniculite,  A control options
analysis has been initialed to determine regulatory strategy to control asbes-
tiform mineral-contaminated vermiculite, and a substitute analysis is in prep-
aration to evaluate replacements for venniculite products.  Work has also been
initiated on a materials balance to show the mass flow of vermiculite along
with the release of any associated asbestiform mineral, and the development of
a mineralogy profile with a sampling and analysis protocol of vermiculite is
underway to characterize the fibrous materials within vermiculite.

          From the available information on the composition of vermiculite, it
seems there is the possibility that asbestos contamination of vermiculite does
occur, but that it may be difficult to assess the magnitude of the contamina-
tion.  Therefore, the objective of this protocol is to specify the sampling
and analysis procedure to determine the composition of vermiculite, particu-
larly the amount of asbestiform minerals1 present in the vermiculite.  This
   For practical analysis purposes, the specific identification of asbestiform
     minerals will be limited to chrysotile, the amphiboles, and venniculite
     scroll.
                                   A-l

-------
will provide the needed information on the risk to the population exposed  to
asbestifonn minerals from vertniculite at each of the various  stages  of its
commercial distribution.

          The protocol will be conducted in two phases.  The  first phase will
be an in-depth analysis of the asbestiforo fibers present in  and associated
with vermiculite ore, ore concentrates, and beneficiated vermiculite from  the
four major vermiculite mines in the United States and of beneficiated vermicu-
lite from the ports of entry.   Both bulk and air samples will be collected
and analyzed.  The second phase will be a similar analysis of bulk and air
samples from a representative number of exfoliation plants in the United States.
The exfoliation plants where sampling will occur will be statistically chosen
by Exposure Evaluation Division (EED) to include all the major sources of
verraiculite.


II.  Preparation for Sampling

     A.  Inventory Supplies

          1.  All necessary equipment for sampling bulk vermiculite  and air
will be gathered and inventoried.

          2.  Filters to be used for the collection of airborne particles
will be assembled and labeled before samples are obtained.

          3.  Calibration of the pumps will be performed prior to their ship-
ment to the sampling site and recalibrated in the field.

          4.  All supplies will be packed and shipped  to the vermiculite  sam-
pling site at least 2 days in advance of the arrival of the crew.

     B.  Site Investigation

          1.  Survey site - Upon arrival at the site,  the crew chief and
other designated persons will survey the site to determine the location of
the  facility, its boundaries, and the locations of various operations within
the  facility.

          2.  Select sampling points - The crew chief  and other designated
persons will select appropriate points for the collection of ore samples  and
airborne particulates.  Officials of the host plant will be invited to par-
ticipate and assist in the survey and selection of sampling points.


III.  Sampling

     A.  Bulk Material

          1.  Basis  for selection of protocol - No American Society for Test-
ing  Materials  (ASTM) method was found that is directly applicable to this  situ-
ation.  The  following  related methods are used for guidance.
                                   A-2

-------
               a.   American National Standards  Institute  (ANSD/ASTM D  75-71
(1978) Standard Methods of Sampling Aggregates.

               b.   ASTM Designation:  D 2234-72 Standard  Methods  for Collec-
tion of a Gross Sample of Coal.

               c.   ANSI/ASTM E 105-58 (1975)  Standard Recommended Practice
for Probability Sampling of Materials.

               d.   ASTM Designation:  C 702-72  Standard Methods  for Reducing
Field Samples of Aggregate to Testing Size.

               e.   ASTM Designation:  C 516-75  Standard Specifications  for
Vermiculite Loose Fill Insulation.

               f.   BS 812 (British Standards  Institution) Methods for Sam-
pling and Testing of Mineral Aggregates, Sands  and Fillers.

               g.   Other Considerations - The minimum quantity of any sample
should be 5 to 10 times the anticipated analytical needs.  The analytical
needs will vary with particle size and range  from approximately 40 g for fine
material to 1,000 g for 25-mm particle size.  Therefore,  sample size minimums
should range from 400 g to 10 kg.

               Each sample may consist of a composite of  individual sampling
increments representing different times and/or  locations.  Increments will  be
sampled and stored separately with a composite  made under laboratory condi-
tions by combining representative fractions of  each increment.

          2.  Samples to be collected - The objective of  sampling is to ob-
tain samples that arc representative of the operations or sites.   It is an-
ticipated that properties of the materials of similar types will vary with
time, operation and specific mine site origin.   Therefore, to obtain repre-
sentative samples, it is necessary that composite samples be prepared of a
given sample type from individual sample increments, each representing a
specific sample time or site.  It is likely that a historical sample collec-
tion is maintained (by the mine company) from several operation points within
the facility.  If these historical samples are  available, it would be helpful
to obtain selected increment samples for both the preparation of a time aver-
aged composite and a comparison of present to past conditions.

          The number of increment samples to be collected must depend on the
variability of the sample and availability of increment sources,  with a de-
cision made by an experienced sampler depending upon increment availability
and proper sampling procedures.  All decisions  will be documented with copies
sent to the EPA task manager.

               a.  Raw ore and ore concentrates (Phase I)

                     (1)  A bulk sample of the raw vermiculite ore represent-
ing different parts of the mine.
                                   A-3

-------
                    (2)  A bulk sample of the concentrated  ore before bene-
ficiation.

                    (3)  A bulk sample of dust from the  dust  collection
equipment where such equipaent exists.

                    (A)  A water sample from washings  and dust control  opera-
tions.

                    (5)  A bulk sample of concentrated ore  blend (beneficia-
tion feed) before beneficiation.

               b.  Beneficiated vermiculite (Phase I)

                    (1)  A bulk sample of each of five grades of beneficiated
vermiculite.

                    (2)  A bulk sample of material from  one to three inter-
mediate beneficiation processing steps.

                    (3)  A bulk sample of tailing from the  beneficiation
process.

                    (4)  A bulk sample of dust from dust collection equip-
ment.

                    (5)  A water sample from washing and dust control opera-
tions.

               c.  Exfoliated plant samples (Phase II)

                    (1)  A bulk sample of each of the five grades of vermicu-
lite before exfoliation.

                    (2)  A bulk sample of each of five grades of exfoliated
vermiculite.

                    (3)  A bulk dust  sample from dust collection equipment
and other appropriate  related material.

     B.  Air Samples (Phases I and and II)

          1.  General  considerations  - Airborne particulate samples will be
collected at designated points  inside and outside the plant boundaries.  The
sampling will generally follow  the EPA method described in Electron Microscope
Measurement of Airborne Asbestos Concentrations - A Provisional Methodology
Manual, EPA-600/2-77-178, Revised June 1978.This method recommends poly-
carbonate 0.4 urn Nuclepore* filters when possible, but allows for the use of
cellulose acetate  (Milliporeti)  filters.

          There  are advantages  and disadvantages to the use of either Nucle-
poreg or  Millipore® filters.  The sample collected on the smooth polycarbonate
                                   A-4

-------
(Nucleporeft) suface has poor retention efficiency and  the  sample may be  lost
or redistributed during transport.   The cellulose acetate  (Millipore®) filters
requires an ashing procedure and reconstitution on a polycarbonate  filter for
TEH analysis.  Ashing and reconstitution is an extra step  in the procedure
but has the potential advantage of eliminating interfering organic  particle
analysis.  This reduces the need of multiple time sampling to obtain a range
of filter loadings.  Asbestos contamination has been reported in  some lots of
both Nucleporeg and MilliporeQ filters.

          The current consensus of leaders in the field is to favor the  use
of Millipore€> filters for the type of sampling and transport that will be re-
quired on this program.

          The potential presence of asbestos fibers in the filters themselves
will require careful attention to the selection and analysis of filter blanks
and field blanks.

          2.  Control blanks

               a.  Filter blanks - Four filters from each package of 100
filters, one from each box of 25, will be selected by random numbers as
filter blanks.  The  four filters will be quartered and one-fourth of each
combined as  a composite sample.

               b.  Field blanks - One of every  10  filters will be a  field
blank, subjected to  all processing conducted with  an actual air sample  except
for the  sampling itself.

          3.  Sampling procedure - All  sampling,  fixed and personal, will  be
taken  using  37 mm  0.45 (Jm Millipore§  filters backed with 5 (Jtm Millipore® filters
and a  Millipore® support pad.  The sampling rate will be approximately  2 liter/
min with the exact  rate determined periodically throughout the sampling period
by the use  of calibrated flow meters.

          Sampling will be  scheduled  for  8  hr  (or  longer  for ambient and back-
ground samples).   However,  if  the  flow is  found to reduce during sampling,
indicating  that  the filter  is  loaded,  sampling will be stopped and  the  time
and  flow rate  recorded.

           4.  Air  samples will  be  collected -  Personal air  zone samples and
 fixed  samples  located at targeted  areas will  be taken.  The  use of  personal
 samples  will depend on the  individual work patterns and on  the cooperation of
 the  host company.   When possible,  individuals  at each work  station  will be
equipped with personal samplers.

           When possible, air samples  will be  taken which  correspond to  the
 bulk samples (Section III-A-2).   The  following air samples  will be  taken.
 Any variation from these sampling locations will be documented.

                a.   Air samples taken at operations before beneficiation
 (Phase I).
                                    A-5

-------
geographic region.
                    (1)  An  air  sample at the mine during mining.

                    (2)  An  air  sample at dumping or crushing operation.

                    (3)  Air samples  around  the mining  facility.

                    (4)  Air samples  downwind of dusty  operations.

                    (5)  Air samples  along  shipping  lanes.

                    (6)  An  air  sample  as a background  control  within the
               b.   Air samples taken from the ore beneficiation operations.
(Where mining and beneficiation are at the same general location, several of
the samples may be the same.)  (Phase I)

                    (1)  An air sample at each of selected work stations in
the beneficiation operation.

                    (2)  Air samples around the beneficiation plant.

                    (3)  Air samples at grading  (screening) operation:;.

                    (4)  Air samples downwind from dusty operations.

                    (5)  Air samples along shipping lanes.

                    (6)  An air sample  as a background control within  the
geographic  region.

                c.  Air samples taken from the exfoliation operation.   (Phase
ID

                    (1)  An  air sample  from each of selected work stations  in
the  exfoliation operations.

                    (2)  Air samples around  the  exfoliation plant.

                    (3)  Air samples downwind  from dusty  operations.

                d.   A  meteorological station  will be installed  on-site  to col-
 lect air speed and direction data throughout the sampling period.


 IV.   Sample Handling

      A.  Bulk Samples

           The increment samples will be shipped to  a  central  laboratory.
 Each increment sample will be divided by appropriate  procedures (riffle di-
 vided or cone and quarter).  Part of each increment will  be retained and the
                                    A-6

-------
remainder combined with other appropriate increments  to form a  composite  sam-
ple.  The composite will be mixed and split (riffle or cone  and quartered)  to
provide appropriate split analytical samples.   The  composite samples  will be
properly designated and submitted for analyses.

     B.  Air Samples

          1.  Special handling - When sampling is completed, the filter
cartridge will be turned to a position with the filter horizontal and the
collection surface up, the cartridge disconnected from the pump, the  car-
tridge cover replaced, and the inlet and exit holes plugged.  This horizontal
filter position will be maintained during transport and storage.  The car-
tridge will be placed in a special container for transport.

          2.  Each filter will be divided and each portion will be taped to
the bottom surface of the petri dish and delivered to different laboratories
to provide for replicate analysis.


V.  Sample Analysis

     A.  Bulk Sample Analysis

          The analysis protocol for the bulk vermiculite samples will include
parallel approaches which, to a degree, support one another.  However, because
of the great differences in the detection limits of the different methods,
the justification of some approaches is their simplicity as preliminary
screening procedures rather than their sensitivity.  X-ray diffraction of the
unfractionated samples is an example of a simple procedure with limited sensi-
tivity.  These methods may serve to identify some samples with gross quanti-
ties of asbestos and eliminate the need for continued analysis.

          1.  Unexfoliated vermiculite, before and after beneficiation

               a.  Examine the sample as received with a low power (30X)
stereomicroscope for quantities of visible fibers.

               b.  If  fibers are observed, estimate the weight  (%) of fibrous
material.   If appropriate, remove  (hand pick) the asbestos  from the  sample
and weigh.

               c.  Identify the isolated asbestiform mineral by appropriate
means  (PLM, XRD, etc.).

               d.  To  isolate the  fine fibers from vermiculite, start with a
sample quantity  depending  on particle size.  Place the sample  in a specified
beaker size and  add  10 times the  sample weight of prefiltered  isopropyl al-
cohol.

               The  sample  quantities, isopropyl  alcohol volume and beaker
sizes  to  be used are  as  follows:
                                   A-7

-------
                                                            Tall  Form
           Sample                 Grams        IPA         Beaker (ml)
Grades 1 and 2                      40         400            1,000

Grades 3 and 4                      20         200              400

Grade 5a                            40         400             1,000

Unbeneficiated material and         40         400             1,000
  other tailings, etc.
a  Grade 5 is expected to have more variability than the other grades.

               Place the beaker in an ultrasonic bath,  stir,  allow the  large
particles to settle (during ultrasonic treatment) and withdraw aliquot  por-
tions from near the center of the liquid for optical microscopic analysis
(i.e., PLM) and to prepare a series of Nucleporeti filters for EM analysis.
Serial dilution may be required to obtain optimum filter loading.

               e.  The NucleporeQ filter with suspended fines will be used  to
prepare a TEH grid by the EPA carbon-coated Nuclepore®  filter technique.

               f.  Make fiber count - Determine chrysotile or amphiboles.
Count 100 fibers or 10 grid of 200 mesh screen.  Determine the limit of de-
tection and count more grids if necessary.

               g.  Identify specific amphiboles using selected area electron
diffraction or zone axis selected area electron diffraction plus energy dis-
persive X-ray analysis.

               h.  Exfoliate a portion of the beneficiated vermiculite  by
sprinkling no more than a one particle thick layer of sample, in a preheated
(800°C) shallow container and place the container back  into a 800°C oven for
5 sec.  Examine the exfoliated sample as described in No. 2.

          2.  Exfoliate vermiculite (for laboratory expanded samples of Phase I
and for Phase II) - An important feature of the analytical procedure to achieve
high microfiber detection sensitivity is the fractionation of the sample to
remove much of the interfering vermiculite, thereby greatly enriching whatever
asbestiform fibers that may be present.  The basis of fractionation is  the
floatation on water of the exfoliated vermiculite and the wetting and sinking
of the asbestos and other fibers.  This assumes that a  proportionally high
fraction of the fibers are not physically attached to the vermiculite parti-
cles.  This is a reasonable assumption but one that will be verified by the
examination of representative samples of the fraction that floats.
                                   A-8

-------
          Starting with a sample quantity depending on particle size,  or grade,


Vermiculite                      Sample                         Water
   Grade                       Weight (g)                    Voluae (ml)

  1 and 2                          40                           2,000

  3 and 4                          20                           1,000

     5                             40                           2,000

and proceed as follows:

               a.  Float separation - Place the expanded veraiculite in a
2,000 ml plastic beaker and add water.  Stir for 30 sec and skim off the
veraiculite and drain on a 50-mesh screen.  Collect the drain water and re-
turn it to the beaker.  Discard the veraiculite.2

               b.  Disperse the "sink" material with ultrasonic treatment.
Remove an aliquot during treatment for a preliminary PLM examination and for
TEH analysis.  Double dilution may be necessary to obtain proper grid  load-
ing.

               c.  Examine preparation by PLM as a preliminary parallel exam-
ination.3

               d.  Prepare TEM grid by EPA carbon-coated Nuclepore® filter
technique.

               e.  Fiber count - Determine chrysotile, total amphiboles and
vermiculite scrolls.  Count 100 fibers or 10 grids of 200-mesh screen.  De-
termine limit of detection and count more grids if necessary.

               f.  Identify specific amphiboles using SAED plus energy dis-
persive X-ray analysis.

          3.  Miscellaneous bulk samples

               a.  Dust samples

                    (1)  A preliminary examination of the dust sample  will be
made by optical microscopy including PLM for the identification of gross
quantities of asbestiform fibers.  If gross quantitier of fibers are identi-
fied, the quantities will be estimated and the analysis terminated.


7Selected samples will be examined to verify the absence of asbestos in
     this fraction.
3  If PLM examination reveals a gross quantity of identifiable asbestiform
     fibers, the quantity should be estimated and the analysis terminated.
     (Modified during the project to continue analyzing.)
                                   A-9

-------
                    (2)  If the sample is not adequately characterized by PLM,
a portion of the sample will be dispersed in water and filtered for EM analy-
sis.

               b.   Wash water samples - The solids present will be dispersed
in the water and aliquots filtered for appropriate optical and EM analysis.

     B.  Air Samples
                                                               ;
          1.  Portions of selected filters will be used to determine fiber
count by the standard NIOSH procedure using phase nicroicopy.

          2.  The major analysis of the air samples will basically follow
that specified in the EPA document, "EPA-600/2-77-178, Revised June 1978,
Electron Microscope Measurement of Airborne Asbestos Concentrations - A
Provisional Methodology Manual.
                                   A-10

-------
                   APPENDIX B





DETAILED ANALYSIS PROCEDURES AS SUBMITTED BY IITRI

-------
                                 PROCEDURES


BULK SAMPLE ANALYSIS

     Quantitative analysis requires that valid and rigorous  procedures  be
used during all phases and steps of a procedure and that these procedures  be
well-defined before work on the first sample is begun.   The  approach and logic
used by IITRI was based on:

     •  A study protocol prepared by MRI,

     •  Discussions of the protocol with MRI, and

     •  Discussion on procedures with Ontario Research Foundation (ORF).

The bulk sample procedure is presented in Figure B-l.   Where we note that the
first operation is, as with any sample, sample log-in.   The  bulk sample is
then subdivided for two distinct series of sequential  steps.  The first begins
with analysis of the sample "as received" for gross (defined for this study
as > 1% by weight) fiber contamination and characterization  by polarized light
microscopy.  Samples which are not found to be grossly contaminated are moved
into the steps of isopropyl alcohol beneficiation and  electron microscopy
analysis for fiber content.

     A parallel screening test for the second series of steps is whether the
sample received is an exfoliated vermiculite or not.  If it  is exfoliated, no
work is needed; if not, the sample is thermally exfoliated,  the product is
beneficiated, and the "sink" fraction analyzed by electron microscopy.

     In the subsections which follow, IITRI describes  the procedures used for:

     •  Sample splitting

     •  Optical microscopy

          - Preliminary inspection
          - Sample separations
          - Polarized light microsocpy
          - X-ray diffraction

     •  Electron microscopy

          - Beneficiation
          - Sample preparation
          - Electron microscopy analysis
   Task 32—Study Protocol for the Collection and Analysis of Vermiculite
     and Related Samples for the Evaluation of Fiber Content with Emphasis
     on Asbestiform Fibers (Revised November 13. 1980).
                                   B-l

-------
                    Saapl* lUcalpc
                      •nd Lo((ln|
             FUt
                        MffU
                    (Utatn B«l«ac«)
Prtllminiry
   FUt
                       1PM
                                     THOMAL
                                                                         Hold for
                                                                        Preliminary
                                                                           FLH
                               IPA Sink
                            to Obtlln Finn
                              by Plp«tt«
                               Dllutt.
                               Fllttr.
                                 Dry
                            To EM Protocol
                Figure  B-l.   Flow  chart for bulk saarple analysis.
                                            B-2

-------
SAMPLE SPLITTING

     The samples were split into aliquots using a spinning riffler.2  The
riffler is a rotating tray containing sample receivers.   As the tray rotates,
the receivers extract a sample from the flowing powder streaa.   This time-
averaged sample consisting of many small aliquott produces a sample free of
biases due to segregation variation in aerodynamic diameter and the powder's
flow properties.

     Each fraction collected was placed in a clean, glass cream jar, labeled
with the IITRI sample number and submitted for analysis or stored.   IITRI
riffled a minimum of four fractions from each sample—one each for PLM, al-
cohol beneficiation, thermal exfoliation, and a back-up sample.  The target
size for each sample was:

     •  Twenty grams for vermiculite Grades 3 and 4.

     •  Forty grams for all others, including vermiculite Grades 1, 2, and
        5.

OPTICAL MICROSCOPY

     The objectives of the polarized light microscopy analyses were to:

     •  Determine if fibers were present,

        Identify the fibrous phases detected,

     •  Determine the concentrations of asbestifortn phases in the bulk sample,
        and

        Identify the prismatic mineral phases present that could fracture to
        yield "fibrous" particles.

     To achieve these objectives,  several sample preparation steps  and sup-
plementary analyses are used as integral parts of  the polarized light micro-
scopy analysis.  The sample separation steps enhance the  (semi-)quantitative
aspects of microscopical analyses  which rely heavily on estimations of com-
ponent concentrations.  The supplementary analyses, principally x-ray dif-
fraction, were  conducted to establish irrefutable  identities of phases—
especially those in a fibrous habit.

Preliminary  Inspections

     The  bulk sample portions submitted for polarized light microscopy  (PLM)
were first inspected with  a low power stereomicroscope to determine the number
of different mineral phases present, the associations of  the various phases,
and the presence of fibrous phases.  This preliminary inspection also served
to determine which  sample  separation step  (hand-picking of fibrous  phases, or
    ASTM C702  71T, Tentative Method  for Reducing Field Samples of Aggregate
      to Testing  Size.
                                    B-3

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heavy liquid separation) should proceed first.   Notations  on sample  color,
texture and general particle size ranges were made at this tine.

Sample Separations

     The objective of the sample separations was to concentration any fibrous
phases to facilitate both the phase identification and quantitation  tasks.
Subsamples for the separation procedures were obtained by  coning and quarter-
ing* the sample fraction submitted for PLM analysis.  The  entire PLM sample
fraction was poured out of its container onto a clean piece of foil  and
quartered with a broad-bladed spatula.  The desired subsample size (one or
two quarters) was retained on the foil and the  remainder of the PLM  sample
was returned to its container.  For those samples that received a duplicate
separation analysis, the coning and quartering  was repeated.

Hand-Picking--
     When the preliminary inspection revealed the presence of several bundles
of fibers at least 1 mm in diameter and 3 ran in length, hand-picking of the
fibrous phase(s) with a fine-pointed tweezers was the first separation step
performed.  The separation subsample of the PLM sample was weighed on a piece
of tared foil and then spread to a monolayer of particles.  While viewing
through the stereomicroscope, the fibers were tweezed from the subsample and
placed in a tared weighing pan.  Mixed particle types containing at least 25%
fibrous material, as well as totally fibrous particles were tweezed.  The pan
containing the fibrous phase as well as.the foil containing the nonfibrous
remainder of the subsample were then reweighed  (to 0.1 nig) and the mass per-
cent of "pickable" fibrous material was calculated.

     When smaller bundles were present, hand-picking was done either after
the first heavy liquid separation step or, for  some samples, was not feasi-
ble.  The procedure for hand-picking fibers from the "sinks" fraction of the
first heavy liquid separation is essentially the same as for the bulk sub-
samples .

Heavy Liquid Separation--
     Nonvermiculite mineral phases, particularly araphiboles and pyroxenes,
were separated from the vermiculite bulk samples on the basis of density us-
ing a simple sink-float method.  The densities  of the mineral phases must
differ by at least 0.2 g/cm2  for this method to work.  Table B-l lists the
specific gravities of vermiculite, some of the  amphibole minerals, and other
mineral contaminants commonly associated with vermiculite.
    See Reference  2, page B-3.
                                   B-4

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             TABLE B-l.  SPECIFIC GRAVITIES OF SELECTED MINERALS
    Mineral
                                Chemical formula
                                             Specific
                                             gravity
Veroiculite
Biotite
Chrysotile
Serpentine
Talc
Anthophyllite
Actinolite
Tremolite
Ferroactinolite
Cummingtonite
Grunerite
Diopside
Hornblende
Quartz
Olivine
(Mg,Ca)0 3(Mg,Fe,Al)3 0(Al,Si)40,0(OH)4
K(Mg,Fe)3(AlSi3010)(OH)2
Mg3Si205(OH)4
Mg3Si2Os(OH)4
Mg3Si4010(OH)£
(Mg,Fe)7Si8022(OH)2
Ca2(Mg,Fe)5Si8022(OH)2
Ca2Mg5Si8022(OH)2
Ca2FesSi8022(OH)2
(Mg,Fe)7Si8022(OH)2
Fe7Si8022(OH)2
CaMgSi206
(Ca,Na)2 3(Mg,Fe,Al)5Si6(Si,Al)2022(OH2)
Si02
(Mg,Fe)2Si04
2.4
2.8-3.2
2.5-2.6
2.3-2.6
2.7-2.8
2.85-3.2
3.1-3.3
3.0-3.2
3.2-3.3
3.1-3.3
3.6
3.2
3.0-3.4
2.65
                                                                 3.27-4.37
     The density separation technique is based on the principal that parti-
cles with a greater density than the liquid they are suspended in will sink
while particles with densities equal to or less than the liquid density will
float in the liquid.  Mineral powder samples subjected to this float-sink
procedure should be composed of single phase grains of fairly uniform size
and less than 1 to 2 mm in diamter.  As particle size approaches subsieve
size (i.e., less than 37 pm), other forces including friction, particle
shape, and thermal turbulence influence the settling characteristics of part-
icles as much as density.  The separation of most bulk samples will improve
if grinding or sieving is performed prior to using the float-sink procedure.
While this would have been true for the vermiculite samples, these steps were
omitted to preserve the integrity of the sample.

     Two density separations were performed on each subsample yielding three
fractions based on density differences.  The separation subsample was first
suspended in 1,1,2,2-tetrabromoethane (THE), specific gravity of 2.97; the
THE "sinks" were the first density separation fraction recovered.  The TBE
"floats" were then suspended in a TBE/isopropanol mixture (specific gravity
of 2.76) yielding two other density-separated fractions, the "2.76 sinks" and
the "2.76 floats."  The procedure is described in detail below.

     The density subsamples were dried for 24 hr at 90°C; then accurately
weighed in tared 250-ml beakers.  Approximately 200 ml of tetrabromoethane
were added, and the mineral powder slurries were vigorously agitated with a
spatula.  The slurries were allowed to stand undisturbed for 12 to 24 hr.
The top 160 to 175 ml of tetrabromoethane containing the "floats" were then
                                   B-5

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decanted into a 400-nl beaker and tetrabromoethane and isopropanol were  added
to produce 300 ml of 2.76 specific gravity liquid.  This  slurry was  agitated
and allowed to separate for 12 to 24 hi until migration of  particles in  the
2.76 sp. gr.  liquid ceased.  The top 200 to 250 ml of liquid  containing  the
"2.76 floats" were decanted into a clean beaker.

     The separated fractions were recovered by filtering  each suspension
through a tared, 0.22 \im pore size, MilliporeB membrane filter.  The re-
covered mineral fractions were dried for 24 hr at 90°C and  weighed.   Since
losses of materials were unavoidable during the decanting and handling,  the
calculations of the mass percent for each density fraction  represented in the
total sample are based on the summed masses of recovered  materials,  rather
than on the subsanple mass determined at the start of the density separations.
For samples from which fibers were hand-picked before the density separations,
the mass of the hand-picked fibers was added to the mass  of the TBE fraction
for calculation of the mass percents of each density separation fraction
represented in the total bulk sample.

     The actual losses occurring in the heavy liquid separation steps were
determined to be 2.2 to 5.5%.  Duplicate separations performed on two of the
samples indicated the density fraction data were reproducible to within 5%.

Polarized Light Microscopy

     A portion of the unseparated sample and of each separation fraction were
dispersed in a standard immersion oil (n_ = 1.515) on a glass slide for PLM
analysis.  Mineral phases present were identified, at least as to mineral
group, by morphological properties and by observation of optical properties;
including extinction angles, birefringence, refractive indices, color and
pleochroism.  Individual particle types removed from subsamples by hand-
picking were mounted in other standard refractive index liquids to allow pre-
cise determination of particle refractive indices.  Comparison of the unknown
mineral particle properties with those of known reference samples and pub-
lished handbook values allowed identification of various mineral types.

     Individual phase concentrations were microscopically estimated in the
density separated subsamples on the basis of relative particle sizes and fre-
quency.  Mass concentration ranges for individual mineral phases were described
as:

     Primary        > 25%
     Major          5 to 25%
     Minor          0.5 to 5%
     Trace          < 0.5%

The  concentrations of the  individual mineral phases in the total bulk sample
were obtained by multiplying the microscopically estimated concentration of
the  phase  in the separation fraction by the mass  fraction the subsample repre-
sented  of  the total sample.  For many samples,  individual mineral phases oc-
curred  in  small concentrations in all the density-separated fractions.
Multiple-phase  particles also contributed to the presence of high density
                                   B-6

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mineral phases in the two lower density fractions.   Thus,  the concentrations
of individual phases within the total sample were determined by sunning the
concentration determined for each density-separated fraction.

X-Ray Diffraction

     Positive identification of mineral phases,  particularly fibrous amphi-
boles, by polarized light microscopy, is difficult.  Therefore, to clearly
establish identities of major and fibrous mineral phases,  x-ray diffraction
(XRD) analyses were conducted on selected separation subsamples and individ-
ual phases hand-picked from separation subsamples.   The major objective of
the XRD analyses was identification of the fibrous phases.

     IITRI used the thin film technique, since this is most suitable for the
very small quantities of materials available from hand-picking.  The thin
films were prepared by filtering the isopropanol suspended material through a
silver membrane (25 mm diamter, 0.45 pm pore size).  The XRD samples were
ground to -325 mesh in a diamonite mortar prior to the filtration.  As im-
plied above, this technique provides an XRD pattern for material quantities
as low as 0.1 mg; its drawback is that quantitation is not practical due to
preferred orientation of many minerals including amphibole fibers.

     Diffraction patterns were obtained with a Rigaku brand, rotating copper
anode diffractometer operated at 50 kilovolts and lOfl milliamps.  The CuK
x-ray lines, with an averaged wavelength of 1.54184 A, were thus generated.
Most patterns were run at a scan rate of 2°/min.  After conversion of the 20
diffraction angles to d-spacings in angstroms, the sample diffraction pat-
terns were compared to standard diffraction patterns published by the Joint
Committee on Powder Diffraction Standards for mineral identifications.

ELECTRON MICROSCOPY

     The objectives of the electron microscopy analysis were to (a) determine
if respirable asbestos fibers were present; (b) identify the fibers present
within the limitations of the EPA Provisional Method;3 (c) determine the
number concentration of respirable asbestos fibers in the bulk sample; and
(d) estimate the mass concentration of "respirable" fibers in the bulk sam-
ple.

     The steps required to achieve these objectives are:

      •  Beneficiation of vermiculite samples,

      •  Sample preparation, and

      •  Electron microscopy analysis.
3Electron Microscope Measurement of Airborne Asbestos Concentrations:  A
      Provisional Methodology Manual, EPA-600/2-77-178.Available from U.S.
      Environmental Protection Agency, Office of Research and Development
      Technical  Information Staff, Cincinnati, Ohio 45268, Samudra, A., et al.
                                   B-7

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Beneficiation

     Two beneficiation procedures were used for the  saaplei;  one used  isopro-
panol and the other water as a working fluid.   Each  is  described below.

Isopropanol Beneficiation—
     The isopropanol beneficiation procedure was used for those samples  whose
asbestos fiber concentration, as determined during the  PLM analysis, was less
than 1% by weight, and to samples 259-1,  264-1, and  291-1* at the specific re-
quest of MRI.

     This beneficiation required particle-free isopropanol, a sonic bath and
tall form beakers.  The weighed sample was placed in a  tall form beaker of
appropriate size; a volume approximately equal to 10 tines the sample  weight
of filtered isopropanol was added and the beaker and contents put in an ul-
trasonic bath.

     The ultrasonic bath was turned on, the mixture  was stirred using a clean
spatula, the large particles were allowed to settle, and aliquots were with-
drawn from the center of the liquid column.  The aliquots were diluted with a
sufficient quantity of prefiltered isopropanol to permit filtration (30 to 50
ml).  Each aliquot was quantitatively transferred to a Nuclepore® filter
for electron microscopy analysis.

Aqueous Beneficiation—
     One of the objectives of the study is to determine the  fate of the as-
bestos which may be in the run-of-the-mine graded vermiculite.  To determine
the fate of the asbestos, IITRI exfoliated the graded vermiculite samples by
exposing them in an 800°C oven, beneficiated the resulting exfoliated sam-
ples, and used electron microscopy to determine the asbestos content of the
sink fractions.

     Thermal exfoliation is  used  to prepare expanded vermiculite products.
This treatment can  readily be simulated in the laboratory.   A monolayer of
unexfoliated vermiculite is  sprinkled into a preheated shallow  quartz con-
tainer which  is  inserted into an  800°C oven for 5 sec.  After the 5 sec ex-
pire, the dish is  removed, permitted  to cool and the exfoliated vermiculite
is  stored  for analysis.  The process  is repeated until all of the sample  is
exfoliated.

     The exfoliated sample  still  contains  all  of the components originally
present; however,  most of  the varmiculite  phase can  now be removed by an
aqueous  float process.   In  the  float  process,  the exfoliated vermiculite  is
placed  in  a  container, 1 or  2  liters  of filtered, distilled  water is stirred
 for 30  sec  and the "vermiculite floats" removed and  drained  on  a 50 mesh, U.S.
 Standard  sieve.   The drain  water is  collected  and returned to  the original
 container,  and the vermiculite  floats are  discarded.

      The  water  (in its container) is  then  placed  in  the  sonic  bath, soni-
 cated,  and aliquot samples  are  removed with a  pipette.  The  procedure used  to
 5Midwest Research Institute sample numbers.
                                    B-8

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prepare filters is identical to that used in the  isopropanol beneficiation,
except that filtered,  distilled water is  substituted  for  isopropanol.

Sample Preparation

     The basic procedures IITRI used to analyze the samples are  documented  in
Electron Microscope Measurement of Airborne Asbestos  Concentrations:   A Pro-
visional Methodology Manual;3 however, four samples were  analyzed  using a mod-
ified protocol.  Both protocols use identical sample  preparation procedures,
which are discussed below followed by a description of the analytical  proto-
cols.

     The membrane on which the sample is  deposited was air-dried overnight  in
a Class 100 clean workbench; a wedge-shaped portion of the filter  was  cut,
carbon-coated, and 0.3 mm diameter circle was then removed with  a  punch from
the wedge for transfer to a 200 mesh copper transmission  electron  microscopy
grid.  The Jaffe washer technique was used to transfer the sample  to the grid.

     In tne Jaffe washer technique, a stack of 40 clean,  4.4  cm  diameter,
paper filters is placed in a clean glass  petrie dish.  Spectroscopic grade
chloroform is then added until the level  is at the top of the stack of filter
paper.  Several small (but larger than the 0.3 mm diameter grid) pieces of  60
or 100 mesh stainless steel (SS) screen are placed on the stack  of filter
paper.  An orientation mark is placed on  the outside  of the petri  dish, and a
"map" showing the location of each piece  of SS mesh is drawn.   A sample to  be
transferred is placed, carbon-coated side down, onto  a transmission electron
microscope grid and the pair is placed on the center  of a piece  of SS mesh.
The sample identification is noted on the "map."  The procedure  is repeated
until the washer is filled or all samples to be prepared are in place.

     The chloroform level is maintained at the top surface of the stack of
filter paper  for the 24 to 72 hr required to dissolve the Nucleporeti membrane.
The preparation is completed by allowing the residual chloroform to evaporate
from the grid, then placing the grid  in a labeled grid storage box.  All of
the procedures described are performed in a Class 100 clean workbench.

Electron Microscopy Analysis

EPA Provisional Method--
     The prepared samples are examined using a JEOL  100C analytical electron
microscope.   The electron microscope  (EM) is used in the transmission mode to
screen  the sample prior  to the analysis and to perform the enumeration and
sizing  of each fiber located in the  selected grid opening(s).  The scanning
transmission  electron microscopy  (STEM) mode is used to obtain nondispersive
x-ray data at a tilt angle of 40°.
    See Reference  3,  page  B-7.
                                   B-9

-------
     Prior to analysis of the sample,  it is  inspected  at  low  (500X) magnifi-
cation to assure that the majority (80%) or  more)  of the  grid openings  are
clear and the carbon film intact.   The particle  loading is  also  determined at
this time.  Any sample found overloaded, damaged,  or not  adequately cleared
is not used in the analytical process, but is  reprepared  fron either  the
original suspension or the filter, as  appropriate.

     The accepted preparations are immediately counted by randomly selecting
a grid opening(s) and counting, sizing, and  classifying each  fiber found  in
the grid opening.  The fibers are classified as  chrysotile asbestos,  amphibole
asbestos, not asbestos, ambiguous, and no pattern based on morphology and the
selected area diffraction (SAD) pattern.  The SAD patterns are  not recorded
(except a few for documentation) or indexed.  The conparison  is visual and if
the pattern is obviously compatible with one of the asbestos  minerals, the
fiber is so classified.  A nondispersive x-ray pattern is often used a« an
aid in the classification, particularly when nonasbestos  phases capable of
providing false positive fiber identification are known (by PLM, XRD, or fron
geological sources) to be present.

     Similarly, fibers whose SAD pattern characteristics  differ significantly
from asbestos pattern characteristics are classified as "not asbestos," and
those providing no pattern* or indeterminate patterns are classified as "no
pattern" or "ambiguous" fibers, respectively.  These data are recorded, with
the size data taken for each fiber, and is  reported for each fiber observed.

     The  fiber enumeration and sizing  is continued until approximately 100
fibers have been  completed or  10  grid  openings have been examined.  The data
are taken  from two different TEM  grids  whenever possible.

Modified  Provisional  Method--
      IITRI analyzed  four  samples  using a modified Provisional Method  to count
the fibers.   The  method was  modified  to facilitate obtaining statistically
valid  counts, which  in turn  permits estimation of confidence limits  for the
analysis.  The modifications  are  based on discussions with Dr.  E. Chatfield
and one  of our objectives  is  to provide data  for  comparison  of  our results
with  duplicate anayses at Ontario Research  Foundation (OKF).

      As  previously stated,  the modifications  affect the  analysis  of  the sam-
 ple  during electron  microscopy—not during  preparation.  The specific  changes
 are  in the loading requirement and the fiber  identification  criteria.

      The difference  in loading requirement  is in  the  basis for  selection of a
 grid.   IITRI selects grids for analysis based on  total loading  of particles.
 We have found that this  basis facilitates particle and fiber identification,
 although it can cause low fiber counts in samples containing asbestos  at the
 part per million concentration level.
    Fibers which are too close to another particle or to the edge of the grid
      frequently are "ambiguous."
                                    B-10

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     The ORF procedure bases grid selection of a fiber loading (with, of
       >/K UppCr Umit fixcd by total P«rt"le loading) of, ideally, 10 as-
       fibers per grid opening.  Since the objective is to obtain statis-
tically valid counts, this procedure also calls for counting on four grids
prepared from different areas of the filter.  This enhances the statistical
validity of the data.

     It is obvious that using the higher loading requires screening many more
tiDers when the ORF procedure is followed; thus, the IITRI method, which in-
volves classification of each fiber encountered, must be modified.  The ORF
procedure allows screening on the basis of morphology and other information
Known about the samples.  As an example, verniculite scrolls and plates are
common nonasbestos "fibers" in vermiculite samples.  However, they have much
lower contrast than do amphibole fibers and prisms and are readily distin-
guished by an experienced analyst scanning the vermiculite samples.  Thus,
the nonasbestos fibers are passed over, chrysotile is identified on the basis
of its unique morphology and amphibole fibers are identified by morphology
and the compatibility of the fibers' SAD pattern with known amphibole patterns.

     The ORF procedure results in three classifications of fibers analyzed-
chrysotile, amphibole, and unidentified fibers.

Data Reduction--
     The data from each procedure is reduced using similar procedures.  The
fiber concentration in fibers per gram is computed based on the original
weight of vermiculite from which the sample was prepared.  It is computed
using Equation 1:
                                          VA
where CN   = Concentration, fibers per gram
      Nf i = Number of fibers of type i counted
      n '   = Number of grid openings counted
      A*   = Area of one grid opening, cm2
      A|   = Area of filter from which grid was made, cm2
      Wg   = Weight of sample, g
      VT   = Total volume of bonification fluid
      VA   = Ali(iuot volume used for filter preparation.

     IITRI and ORF used similar but different grids.   Those used by IITRI were
extremely  uniform in opening areas and not all openings were measured.   ORF
used a different grid which was not as uniform and measured each grid openine
that was counted.                                                      r«=«j.u8

     The total mass of fibers is estimated using a right  circular prism model
to compute a volume, then multiplying by a density and summing over each fiber
type.  This calculation is shown in Equation 2.   The  mass concentration,  f /»
is computed by substituting the total fiber mass estimate into Equation 1  8
                                   B-ll

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                              n
                         Mf = Z  ? x d2 x S. x e x 108            (2)
                             i=l


where:  Mf = Estimated total fiber mass, f

        d2 = Fiber diameter (projected width), \m
        I  = Fiber length, pm
        e  = Mineral density, g/cm3:  chrysotile = 2.6 g/cm3
                                      amphibole =3.0 g/cm3

Fiber detection limits for any sample can also be computed using Equation 1.
To do this, the value of 1 is substituted for Nf, equivalent to assuming 1
fiber is detected.  All detection limits reported herein are in fibers per
gram.

     When high fiber loadings are encountered, or when the ORF alternate pro-
cedure is used, the average fiber count per grid opening and the standard de-
viation (S) are determined.  These values are computed using standard methods
based on a normal distribution and the fiber count data are then given with
95% confidence limits.

Airborne Fiber Analysis—
     The enumeration and measurement of airborne fibers is accomplished using
two well-defined and established techniques.  The first is the NIOSH specified
phase contrast fiber enumeration by optical microscopy.  The procedures are
described in detail in DHEW (NIOSH) Publication No. 79-127.  The second ana-
lytical method is the U.S. EPA's Provisional Methodology, described in EPA-
600/2-77-178, revised June 1978.  The NIOSH procedure is sunmarized below,
since it was used for analyses on this program; the EPA electron microscope
procedures are identical to the procedure described as Sample Preparation and
Electron Microscopy Analysis (EPA Provisional Method) in the bulk somple pro-
cedures.

Sample Preparation

     Samples to be submitted for phase contrast enumeration are collected on
cellulose acetate (MilliporeS or equivalent) filters using an open face filter
holder.  The sample is prepared for enumeration using one of two techniques--
dissolving the filter in a solution of dimethyl phthalate and diethyl oxalate
containing clean, dissolved membrane for viscosity control4 or by collapsing
the membrane pore structure using a solution of hexane/1,2-dichloroethane/
p-dioxane and rendering the collapsed membrane transparent by exposure to ace-
tone vapors.5  Both techniques end by covering the sample with a cover slip,
with the latter technique requiring a 1.505 refractive index oil.  IITRI uses
the second procedure because it provides a permanent mount with no restric-
tions on the count-time frame.  This preparation procedure is routinely used
by IITRI for proficiency analytical testing (PAT) fiber enumeration.
   Contained in P&CAM 239, recommended by NIOSH.
   Millipore€> Procedure, TS018.
                                   B-12

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Fiber Enumeration

     The fibers on the filter are enumerated using the following protocol.   A
Porton Graticule is used to define counting areas.  A mininua of 20 areas and a
maximum of 100 areas are counted.  After 20 areas have been counted, the
enumeration of fibers is topped when 100 fibers have been enumerated.   Fibers
are enumerated using the following rules:

     •  Fiber is entirely within counting area
          Count—I fiber if length > 5 \tm

     '  Fiber has one end in counting area
          Count—1/2 fiber if length > 5 pm

     •  Fiber crosses two sides of counting area
          Count—no fiber         ,

     •  Fiber does not enter counting area
          Count—no fiber

Note:  All fibers—defined as particles having parallel sides, length to di-
ameter ratio I 3 and length > 5 pm—are enumerated by the NIOSH procedure.
Thus, if the probability is high that nonasbestos fibers are present, the
NIOSH procedure can overstate the actual asbestos fiber concentration.  The
reason for the possible over statement is the fact that phase contrast il-
lumination does not allow the analyst to identify the individual fibers.

     The fiber count data are converted to airborne fiber concentration using
Equation 3:


                                  F  = Vf                      (3)
                                       acVs

where:  FC = Airborne fiber concentration, fibers/cc
        f  = Number of fibers enumerated
        a  = Total counting area, cm2
        Af = Area of filter used for sample collection, cm2
        V  = Volume of air sampled, cc
         s
                                   B-13

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               APPENDIX C





AIR SAMPLES FLOW RATES AND SAMPLE VOLUMES

-------
     The Dupont Model 4000 personal air samplers  were calibrated before  and
after each day of sampling.   The calibration was  done with a  500-nl  soap
bubble meter and a stop watch.   The sampler calibration values  are given in
Table C-l.

     The data for the volume calculation for the  various personal air sanples
are given in Table C-2.

     The flow rates for the stationary samplers were measured at the beginning
of sampling, periodically during sampling and at  the end of sampling.  The
data for the stationary samplers are given in Table C-3.
                                   C-l

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         TABLE C-l.   PERSONAL SAMPLER CALIBRATIONS (EACH VALUE REPRESENTS A MINIMUM OF THREE DETERMINATIONS)
Grace, Libby Montana
Sampler
ID
186172
186173
186174
186175
1-7328
o 2-7334
6-7329
7-7317
Pr?T a
sampling
2.13
2.12
2.09
2.12
2.07
2.16
2.12
2.19
Post-
sampling
1.91
1.92
1.96
1.93
1.89
2.13
1.99
1.99



Grace Mill
Pre-
sampling
2.02
1.96
1.99
1.98
2.02
2.00
2.02
2.01
Post-
sampling
2.07
1.94
2.00
2.01
2.04
2.04
2.07
2.00
Avga
2.04
1.95
2.00
2.00
2.03
2.02
2.04
2.01
Enoree, North Carolina
Grace Mine Patterson
Pre- Post- a Pre- Post-
sampling sampling Avg sampling sampling Avg




1.94 1.99 1.97
1.98 1.92 1.95 1.94 1.93 1.93
1.95 2.00 1.98 1.95 1.94 1.94
1.93 1.93 1.93
a  Values used to calculate sample volume.

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TABLE C-2.  DATA FOR VOLUME CALCULATIONS FOR PERSONAL SAMPLES
Sample
no.
101
121
125
126
128
129
130
131
135
138
139
141
146
148
300
301
304(S)a
305
306
308
310
314
315
320
321
322
324
330
322(S)a
336
337
339
340
34l(S)a
347
349
Sampler
ID
1-7328
186173
7-7317
186175
2-7334
186172
7-7317
186174
186174
186172
2-7334
6-7329
6-7329
186175
2-7334
6-7329
186174
186172
6-7329
7-7317
2-7334
186173
1-7328
2-7334
7-7317
186173
1-7328
1-7328
2-7334
6-7329
186175
186172
6-7329
2-7334
186175
1-7328
Flow
(£/nin)
2.07
2.12
2.19
2.12
2.16
2.13
2.19
2.09
2.09
2.13
2.16
2.12
2.12
2.12
2.02
1.98
2.00
2.04
1.98
2.01
1.95
1.95
1.97
1.95
2.01
1.95
1.97
2.03
2.02
2.04
2.00
2.04
2.04
2.02
2.00
2.03
TiM
stapled
(•in)
186
429
264
278
266
270
130
145
283
138
125
130
261
140
175
121
438
141
362
203
132
146
127
280
238
241
31
141
202
205
246
302
181
79
157
251
Voluae
W
385
909
578
589
575
575
285
303
591
294
270
276
555
297
354
240
876
288
717
408
257
285
250
546
478
470
61
285
408
418
492
616
369
160
314
507
                                                  (continued)
                            C-3

-------
                             TABLE C-2 continued
                                                      Tine
Sample           Sampler           Flow              sampled           Volume
 no.               ID              (£/min)            (min)              (£)


504              2-7334             1.93               185              357
508              7-7317             1.93               132              255
511              6-7329             1.94               194              376
516              7-7317             1.93               188              363
517              2-7334             1.93               192              371
519              7-7371             1.93               177              342
520              6-7329             1.94               130              252
521              6-7329             1.94               184              357
542              2-7334             1.93               129              249
a  304(S), 332(S), and 34l(S) were stationary samples.
                                    C-4

-------
TABLE C-3.  VOLUME CALCULATIONS FOR STATIONARY SAMPLES
Sample
no.
102
103
104
107
108
111
112
113
115
116
119
120
122
123
124
132
134
136
145
147
149
302
307
309
313
316
318
323
328
329
331
334
335
338
342
343
344
345
350
351
352
353
354
Average
flow
(A/rain)
0.97
1.04
2.19
1.90
1.16
2.08
2.05
1.39
0.79
0.90
1.00
2.20
2.36
1.47
0.88
0.96
1.94
0.97
1.09
1.41
1.14
0.74
1.31
1.04
1.81
1.85
1.18
1.54
2.37
2.13
1.52
1.08
0.85
1.94
1.58
2.36
1.05
1.77
0.87
1.26
1.45
1.96
1.59
Time
sampled
(•in)
270
182
178
109
146
177
301
143
321
174
128
299
179
166
343
362
404
114
386
387
369
321
222
321
329
314
320
100
121
387
128
124
94
136
327
328
84
122
331
332
352
322
324
Voluae
(4)
261
189
390
207
169
368
616
199
253
156
128
658
422
244
302
348
784
111
421
545
420
239
291
334
595
582
378
154
287
823
195
134
80
264
516
774
88
216
288
420
511
632
515
                                          (continued)
                       C-5

-------
                             TABLE C-3 continued
                     Average                Time
Sample                flow                 sanpled               Volume
 no-                 U/min)                («in)                 (£)


 502                  1.67                   351                  585
 503                  1.46                   144                  210
 506                  2.23                   123                  274
 513                  1.30                   145                  188
 515                  1.70                   175                  299
 518                  1.76                   342                  601
 523                  1.72                   348                  599
 525                  2.19                   342                  748
 527                  2.13                   345                  735
 528                  1.02                   144                  147
 531                  2.08                   144                  300
 540                  2.04                   343                  701
                                   C-6

-------
                  APPENDIX D





INCREMENT BULK SAMPLES COLLECTED AND COMPOSITED

-------
     Most of the samples submitted for anaysis were composites  of increment
samples.   To prepare the composite samples each increment sample was riffled
to obtain a representative fraction of the increment.   Approximately equal
weight fractions of each increment fraction were combined to make a composite
oanple.  The composite sample was then mixed and riffled to produce four equal
samples.   One of the fourths was set aside and retained as a control.  One of
the fourths was again riffled to produce two-eights of the original conposite.
The two-eightho were combined with the two-fourths so that the composite was
divided into 1/4, 3/8, and 3/8 of the original.  The "1/4" was retained at
MRI: one "3/8" was sent to IITRI; the other "3/8" was sent to Ontario (ORF)
for analysis.

     Each of the increment samples was assigned a sample ID number.  Tables
D-l, D-2, and D-3 lists the increment samples fron the three collection lo-
cations that were processed into compositeo.  Table D-4 lists the sacples that
were not processed.
                                    D-l

-------
TABLE D-l.  INCREMENT AND COMPOSITE SAMPLES FROM LIBBY, MT, GRACE
Sample
description
Grade 1
Grade 1
Grade 1
Grade 1
Grade 1
Grade 1
Grade 1
Grade 1
Grade 1
Grade 1
Grade 1
Grade 1
Grade 2
Grade 2
Grade 2
Grade 2
Grade 2
Grade 2
Grade 2
Grade 2
Grade 2
Grade 2
Grade 2
Grade 2
Grade 3
Grade 3
Grade 3
Grade 3
Grade 3
Grade 3
Grade 3
Grade 3
Grade 3
Grade 3
Grade 3
Grade 3
Date
collected
10/7/80
10/8/80
10/9/80
10/10/80
10/13/80
10/14/80
10/15/80
10/16/80
10/17/80
10/21/80
10/23/80
Composite
10/7/80
10/8/80
10/9/80
10/10/80
10/13/80
10/14/80
10/15/80
10/16/80
10/17/80
10/21/80
10/23/80
Composite
10/7/80
10/8/80
10/9/80
10/10/80
10/13/80
10/14/80
10/15/80
10/16/80
10/17/80
10/21/80
10/23/80
Composite
Sample
ID
151
152
153
154
155
156
157
158
159
160
161
270
162
163
164
165
166
167
168
169
170
171
172
276
173
174
175
176
177
178
179
180
181
182
183
259
Sample
weight
(8)
1,030
1,002
1,002
1,000
1,001
999
1,002
1,009
1,000
798
991

1,001
1,006
1,004
1,004
1,004
1,002
956
1,002
1,002
873
992

999
1,002
1,002
1,002
1,003
997
1,003
1,000
997
1,000
964

Weight
for composite
(g)
126
125
126
125
125
125
125
125
125
125
125

125
125
125
125
125
125
125
125
125
125
125

133
113
121
122
127
124
129
124
124
124
125

                                                  (continued)
                              D-2

-------
TABLE D-l continued
Sample
description
Grade 4
Grade 4
Grade 4
Grade 4
Grade 4
Grade 4
Grade 4
Grade 4
Grade 4
Grade 4
Grade 4
Grade 4
Grade 5
Grade 5
Grade 5
Grade 5
Grade 5
Grade 5
Grade 5
Grade 5
Grade 5
Grade 5
Grade 5
Grade 5
Head feed8
Head feed8
Head feed"
Head feed3
Head feed*
Head feed8
Head feed"
Head feed*
Head feed8
Head feed8
Date
collected
10/7/80
10/8/80
10/9/80
10/10/80
10/13/80
10/14/80
10/15/80
10/16/80
10/17/80
10/21/80
10/23/80
Composite
10/7/80
10/8/80
10/9/80
10/10/80
10/13/80
10/14/80
10/15/80
10/16/80
10/71/80
10/21/80
10/23/80
Composite
10/8/80
10/9/80
10/10/80
10/13/80
10/14/80
10/15/80
10/16/80
10/17/80
10/23/80
Composite
Sample
ID
184
185
186
187
188
189
190
191
192
193
194
282
195
196
197
198
199
200
201
202
203
204
205
264
223
224
225
226
227
228
229
230
231
291
Staple
weight
(g)
1,000
1,004
997
1,002
1,001
1,000
1,000
1,022
1,000
999
1,002

1,000
1,001
1,005
999
998
1,000
1,000
1,000
997
995
1,000

958
965
955
951
953
947
949
950
1,000

Weight
for coaposite
(8)
125
125
125
125
125
125
125
125
125
125
125

125
125
124
125
129
129
124
126
124
126
125

125
125
125
125
125
125
125
125
125

                        (continued)
   D-3

-------
                            TABLE D-l continued
Sample
description
Extractor
Extractor
Extractor
Extrictor
Extractor
Extractor
Extractor
Extractor
Extractor
Dust, screening plant
Dust, screening plant
Dust, screening plant
Dust, screening plant
Dust, screening plant
Dust, screening plant
Dust, screening plant
Dust, screening plant
Dust, mill baghouse
Dust, mill baghouse
Dust, mill baghouse
Dust, mill baghouse
Dust, mill baghouse
Dust, mill baghouse
Dust, mill baghouse
Dust, mill baghouse
Dust, mill baghouse
Date
collected
10/8/80
10/9/80
10/10/80
10/13/80
10/14/80
10/15/80
10/16/80
10/17/80
Composite
10/8/80
10/9/80
10/10/80
10/13/80
10/14/80
10/15/80
10/17/80
Composite
10/8/80
10/9/80
10/10/80
10/13/80
10/14/80
10/15/80
10/16/80
10/17/80
Composite
Staple
ID
250
251
252
253
254
255
256
257
294
206
207
208
209
210
211
212
288
215
216
217
214
218
219
220
221
297
Staple
weight
(8)
870
860
852
860
860
893
887
890

1,008
1,000
998
1,230
996
965
980

1,006
998
1,003
1,009
977
989
1,002
1,004

Weight
for composite
(1)
125
125
125
125
125
125
125
125

125
125
125
125
125
125
125

125
125
125
125
125
125
125
125


All "head feed" samples contained rocks too large to pass through the
  channels in the riffle box.  These were separated out, weighed sep-
  arately, and retained at MRI.

-------
TABLE D-2.  INCREMENT AND COMPOSITE SAMPLES FROM EKOREE. SC. GRACE
Sample
description
Grade 3
Grade 3
Grade 3
Grade 3
Grade 3
Grade 3
Grade 3
Grade 3
Grade 4
Grade 4
Grade 4
Grade 4
Grade 4
Grade 4
Grade 4
Grade 4
Grade 5
Grade 5
Grade 5
Grade 5
Grade 5
Grade 5
Grade S
Grade 5
Mill feed + 100 mesh
Mill feed + 100 mesh
Mill feed + 100 mesh
Mill feed + 100 mesh
Mill feed + 100 mesh
Mill feed + 100 mesh
Mill feed + 100 mesh
Mill feed + 100 mesh
Grade 3 exfoliated
Analysis ID
Grade 4 exfoliated
Analysis ID
Date
collected
10/27/80
10/28/80
10/29/80
10/30/80
10/31/80
11/1/80
11/2/80
Composite
10/27/80
10/28/80
10/29/80
10/30/80
10/31/80
11/1/80
11/2/80
Composite
10/27/80
10/28/80
10/29/80
10/30/80
10/31/80
11/1/80
11/2/80
Composite
10/27/80
10/28/80
10/29/80
10/30/80
10/31/80
11/1/80
11/2/80
Composite
11/5/80

11/5/80

Sample
ID
389
390
391
392
393
394
395
430
396
397
398
399
400
401
402
433
403
404
405
406
407
408
409
427
375
378
379
381
384
386
388
436
424
439
422
442
Simple
weight
(8)
1,538
2,584
2,445
1,900
2,584
2,682
2,788

1,490
2,450
2,380
2,390
2,715
2,610
3,005

1,729
2,459
2,590
2,185
2,700
2,490
2,770

451
881
776
709
958
836
792

203

260

Weight
for composite
(8)
120
120
125
125
125
125
126

125
125
125
125
125
125
125

123
126
119
125
125
125
129

225
225
225
225
225
225
225





                               D-5

-------
   TABLE D-3.  INCREMENT AND COMPOSITE SAMPLES FROM EMOREE. SC. PATTERSON

Sample
description
Ungraded
Ungraded
Ungraded
Ungraded
Ungraded

Date3
collected
11/6/80
11/6/80
11/6/80
11/6/80
Composite

Sample
ID
567 '
568
569
570
573
Sample
weight
(g)
1,770
1,700
1,186
1,780

Weight
for composite
(8)
250
250
250
250

a  Increments taken at 2 hr intervals.
                                    D-6

-------
            TABLE D-4.   BULK SAMPLES THAT WERE  COLLECTED BUT NOT
	SUBMITTED FOR ANALYSIS	

              Staple description                      Number of  increments


Grace, Libby, under 90  mesh                                    9

Grace, Libby, coarse tails                                     9

Grace, SC, mill feed, under 100 mesh                           7

Grace, SC, dryer composite                                     7

Grace, SC, wet scrubber discharge                              1

Grace, SC, composite total tails                                1

Grace, SC, Lanford mine composite                               1

Grace, SC, Foster mine composite                                1

Grace, SC, No. 4 concrete aggregate, stabilized                 1

Grace, SC, No. 3 masonry insulation                             1

Patterson, SC, raw ore prescreen                                1

Patterson, SC, raw ore postscreen                               3

Patterson, SC, raw ore multiple grab from
  main ore pile                                                 1

Patterson, SC, main waste pile                                  4

Patterson, SC, preexfoliated waste                              4

Patterson, SC, bagged product                                   4
                                    D-7

-------
                       APPENDIX E





PHOTOMICROGRAPHS AND TEM MICROGRAPHS OF SELECTED SAMPLES

-------
     1.  Photomicrographs (IITRI) (p. E-2 to E-17)  of selected samples.
All photomicrographs were taken with slightly uncrossed polars unless
otherwise indicated.

     2.  TEM micrographs (ORF) (p. E-18 to E-25) of selected samples
to illustrate the types of particles observed in samples of vermicu-
lite from the various locations represented in this study.  It should
be noted that these micrographs were taken using specimen grids pre-
pared for Illustration purposes only and the particle loadings are
considerably heavier than those required for TEM evaluation.
                                   E-l

-------
259-I-TBS; 52X.  Unevenly fractured fragments of dark green diopside and
  augite.
259-1-2.76 float; 84X.  Large flakey particles are vermlculite with white
  stress lines.  Arrow points to a flake of talc intergrown with tremolite-
  actinolite fibers.

                                     E-2

-------
259-I-TBS-Flbers (ground); 208X.  Large bundle in the center Is unquestionably
  fibrous tremolite-actinolite.  Note the (white) interference colors of
  fibers growing at angles to the main fiber bundle which has been rotated to
  an extinction position (and is therefore gray).

259-I-TBS-Fibers (ground); 208x.  This parallel-lanellated prism morphology of
  tremolite-actinolite was found within hand-picked fiber bundles.
                                     E-3

-------
259-1-2.76 sink; 208X.  Calcite (bright white) growing in a pseudoraorphically
  fibrous crystal habit within tremolite-actinolite fiber bundles,  Some cal-
  cite crystals (arrows) could be fractured to yield "fibers".
259-1-2.76 float; 84X.   Arrow points to a flake of lanellated quartz.   The
  flakey, lamellated morphology was caused by the quartz forming inbetween
  vermiculite plates.

                                      E-A

-------
264-I-TBS; 208X.  Arrows point to tremolite-actlnolite In two different crys-
  tal habits—the parallel, lamellated prisms and truly fibrous material.  The
  mottled coloring of the fiber bundle is due to the various angles at which
  the individual fibers are intergrowing with each other.

264-I-TBS; 208X.  The circle outlines one tremolite-actinolite particle
  which contains 2 different crystal habits—the parallel,  latnellated prisms
  on one end and matted, intergrown fibers (white portion)  on the other end.


                                     E-5

-------
                                            •

264-1; 84X.  The large elongated particle in the center is fibroua tremolite-
  actinolite with inclusions(arrows) of prismatic tremolite-actinolite.  The
  large flakey white particle (arrow) is a sheet of quartz adhering to vermi-
  culite and was apparently growing inbetween vermiculite plates.
291-I{ 84X.   The friability of the tremolite-actinolite fiber bundles is
  demonstrated here.   Simple dispersion of the sample resulted in abrasion
  of numerous smaller fiber bundles from the large bundles present.

                                     E-6

-------

430-I-TBS (minimal grinding); 208X.  The tremolite-actinolite, hornblende and
  anthophyllite ampttibole fragments are mostly Irregular to chunky prisms.
  Some slender prisms which could yield particles classifiable as fibers
  are present.

430-1-2.76 sink  (after grinding); 208X.  Most of the prismatic to near fibrous
  amphlbole separated into this density fraction because it was so intimately
  intergrown with vermiculite and talc.

                                      E-7

-------
430-1-2.76 float (ground); 208x.   Although optical and morphological proper-
  ties of the mottled phase depicted were consistent with serpentine minerals
  XRD data ruled out serpentine as its identity.  Mixed layer vermiculite-
  hydrobiotite was identified in the XRD work.
427-I-TBS; 84X.  Several large lamellated, parallel prisms of tremolite-
  actinolite and anthophyllite are visible.

                                     E-8

-------
427-I-TBS (ground); 208X.  Crushing of the large amphibole prisms produced
  prisms with splinter fragments that could morphologically be defined as
  fibers.

427-I-TBS-Flbers (ground); 208X.  Crushing of coarse "fibers" produced mostly
  prismatic material.  Arrows point to the numerous vermlculite and talc
  plates Intergrown within "fiber" bundles,

                                     E-9

-------
427-1-2.76 sink; 208X.   The white portion of the circled particle is talc.
  The remainder is (lamellated) prismatic anthophyllite.  Numerous flakes of
  talc intergrown with anthophyllite were found in this fraction.
A36-1; 82X.  The amphiboles are mostly chunky and prismatic in this sample,
  Arrow points to tremollte composed of rather thick, lamellated prisms.

                                     E-10

-------
436-I-Flbers (ground);  208X.  Truly fibrous anphlbole an well as very chunky,
  prismatic particles were produced when particles nacroscopically classifiable
  as fiber bundles were ground.

 436-I-TBS-green,  glassy  (ground);  208X.  This phase was a mixture of horn-
   blende  and  tretnolite-actinolite.  The amphiboles' morphologies were
   predominantly chunky prlsma.
                                     E-ll

-------
436-I-TBS-milky green (ground); 208X.  Mineral grains composed of this tretno-
  lite-hornblend mixture were irregular in shape and rough.  Appearances of
  crushed fragments Indicated that the grains were composed of agglomerated
  smaller crystals which themselves were irregularly grown.

 436-1-TBS-colorless,  glassy  (ground);  208X.  The predominant material is
   fluorapatite—high  contrast,  conchoidally  fractured particles.
                                     E-12

-------
573-I-TBS; 82X.  Non-verraiculite phases were mostly chunky, prismatic amphi-
  bolea, iron oxides (black) and fluorapatite (rounded, gray particles).
 573-I-TBS  (ground);  208X.  Grinding did  result  in  fracture of some amphibole
   grains into elongated  fragments morphologically  classifiable as fibers.
   Most of  the amphibole  fragments retained  chunky, prismatic morphologies.
                                     E-13

-------
267-I-TBS; 82X.  Fibrous and prismatic amphiboles (arrows) are present with
  diopside.

 276-I-TBS-milky green (ground);  208X.   Like  the milky green  mineral  grains of
   436-1,  the milky green grains  of this sample were  composed of multiple,
   poorly  formed amphibole crystals.   Unlike  the 436-1 sample,  the  individual
   crystals in this sample exhibited mostly fibrous morphologies.
                                     E-1A

-------

276-I-TBS-dark, green glassy (ground); 208X.  The pyroxene, diopslde, exhibits
  some concholdal as well as prismatic fracture patterns.
                                                            '
 294-I-TBS; 82X.  Small amphibole fiber bundles and large amphlbole prisms are
   present.  Note the layered crystal growth of the fractured tremolite-
   actinollte fragment (arrow).
                                      E-15

-------
288-1; 52X.  The mottled coloring of this large trenolite-actinolite fiber
  bundle is due to the non-parallel, radiating growith pattern of the indivi-
  dual fibers in the bundle.
                                                             •
 288-1 (fines); 208X.  Much abrasion and disintegration of large fiber bundles
   has obviously occurred in the processing of the vermicullte, as indicated
   by the numerous very fine fibers present.
                                      E-16

-------
297-1; 208X.   The fine,  single fibers here were abraded from larger trenolite-
  actinolite  fiber bundles.
                                      E-17

-------
                                      ' 1.0 Mm
Transmission electron micrograph showing
typical particulate matter found in vater
suspension after laboratory exfoliation
of Sample 264-0, Grace, Libby, Montana,
Grade S (composite).
            E-18

-------
                                        pm
Transmission electron micrograph showing
typical partlculate matter found In water
suspension after laboratory exfoliation
of Sample 264-0, Grace, Libby, Montana,
Grade 5 (composite).
        E-19

-------
Transmission electron micrograph shoving
typical particulate matter found in water
suspension after laboratory exfoliation
of Sample 264-0, Grace, Libby, Montana,
Grade 5 (composite).
       E-20

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,r-v   >rT>v  •..•
'V--.-     -•,>:..,• ••^•V
-  •' "^ * • •
               Transmission electron micrograph showing
               typical particulate matter found in water
               suspension after laboratory exfoliation
               of Sample 427-0, Grace, Enoree» South
               Carolina, Grade 5  (composite).
                      E-21

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                                     1.0 um
Transmission electron micrograph showing
typical partlculate natter found In water
suspension after laboratory exfoliation
of Sample 427-0, Crace, Enoree, South
Carolina, Grade 5 (composite).
         E-22

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            iprs—  r                .        »
,  ,,,'•-,, A  • /°,  *  ^  j= *    «,  <-
                                                    . 1.0  um
                 Transmission  electron micrograph showing
                 typical  particulate matter found in water
                 suspension  after laboratory exfoliation
                 of  Sample 427-0, Grace,  Enoree,  South
                 Carolina, Grade 5 (composite).
                         E-23

-------
•: ;   ".  .;.<'• •'''^/£'f.v*S& •'.•:•
'••"v»•>-.v-v-  ;j^«K£;
                                 .0 urn
          Transmission electron micrograph showing
          typical participate matter found In water
          suspension after laboratory exfoliation
          of Sample 573-0, Patterson, Enoree, South
          Carolina, Ungraded, Dried Ore (composite).
              E-24

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      :*> v
           *   %  •
            • —- »•

• ••-•^ ;jfc
• v..
                   •. *
                 " V*- '
                    >5-
                       •1:
                                  1 ". /V
                                  ',.•>»
                                 :•>>
                                 1.0 um
        Transmission electron micrograph showing
        typical particulate matter found in water
        suspension after laboratory exfoliation
        of Sample 573-0, Patterson, Enoree, South
        Carolina, Ungraded, Dried Ore (composite).
              E-25

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