oEPA
           United States
           Environmental Protection
           Agency
           Office of Acid Deposition,
           Environmental Monitoring and
           Quality Assurance
           Washington DC 20460
EPA/600/4-87/041 b
December 1987
           Research and Development
Direct/Delayed Response
Project: Field
Operations and
Quality Assurance
Report for Soil
Sampling and
Preparation in the
Southern Blue Ridge
Province of the United
States
Volume II. Preparation

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                                                     EPA/600/4-87/041b
                                                     December 1987
           Direct/Delayed Response Project:
   Field Operations and  Quality Assurance  Report
       for Soil Sampling  and Preparation  in  the
Southern  Blue Ridge  Province of  the United States
                   Volume II Preparation
                  M.F. Haren and R,D, Van Re mo rt el
                           A Contribution to the
                    National Acid Precipitation Assessment Program
                          U.S. Environmental Protection Agency
                          Begion 5, Library (5PL-16)
                          230 S. Dearborn Street,. Baom
                                 if*  £0604
                              U.S. Environmental Protection Agency
                      Office of Modeling, Monitoring Systems, and Quality Assurance
                         Office of Ecological Processes and Effects Research
                              Office of Research and Development
                                  Washington, D.C. 20460
                   Environmental Monitoring Systems Laboratory, Las Vegas, Nevada 89193
                       Environmental Research Laboratory, Corvallis, Oregon 97333

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                                        Notice


     The information in this document has been funded wholly or in part by the United States
Environmental  Protection Agency under Contract Number 68-03-3249 to Lockheed Engineering &
Sciences Company.  It has been subject to the Agency's peer and administrative review, and it has
been approved for publication as an EPA document.

     The mention of trade names or commercial products does not constitute endorsement or
recommendation for use.

     This  document is  one volume of a set which fully describes the Direct/Delayed Response
Project, Southern Blue Ridge and Northeast soils surveys.  The complete document set includes the
major data report, quality assurance plan, analytical methods manual, field operations reports, and
quality assurance reports.  Similar sets  are being produced for each Aquatic Effects Research
Program component project.  Colored covers,  artwork, and the use of the project name in the
document title  serve to  identify each companion document set.

     The correct citation of this document is:

Haren, M. F. and R. D. Van Remortel. 1987. Direct/Delayed Response Project: Field Operations and
     Quality Assurance Report for Soil Sampling and Preparation  in the Southern Blue Ridge
     Province of the United States EPA 600/4-87/041b.  U.S. Environmental Protection Agency, Las
     Vegas, Nevada. 24 pp.

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                                       Abstract


     The  Direct/Delayed  Response  Project  Soil Survey includes the mapping, characterization,
sampling,  preparation, and analysis of soils in order to assess  watershed response to acidic
deposition within various regions of the United States. Soil samples from the Southern Blue Ridge
Province were transported to preparation laboratories for processing before delivery to analytical
laboratories. This document summarizes procedural and operational compliance with the protocols
used at the preparation laboratories. Deviations from the protocols and difficulties encountered
are identified  and discussed.  Recommendations are made for program improvement.

     A review of the soil data  suggests  that the integrity of the soil samples was maintained
during  the preparation activities.  In most  cases, laboratory personnel adhered to protocols.

     This report was submitted in partial fulfillment of contract number 68-03-3249 by Lockheed
Engineering and Sciences Company, Inc. under the sponsorship of the U.S. Environmental Protection
Agency. The report covers a period from March, 1986 to December, 1986, and work was completed
as of October, 1987.

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                                     CONTENTS
                                                                                   Page

Notice  	   ii
Abstract	  iii
Figures	  vii
Tables	viii
Acknowledgments	  ix


     1  Introduction  	   1

        Overview	   1
        Objectives	  2

     2  Sample Preparation Methods and Analysis	  5

        Sample drying	  5
        Moisture determination	  5
        Crushing and sieving	  5
        Rock fragment determination	  5
        Soil homogenization  	  5
        Qualitative test for inorganic carbon	  5
        Bulk density determination	  6

     3  Preparation Laboratory Operations	  7

        Sample receipt and storage	  7
        Equipment inventory  	  7
        Sample drying	  8
        Moisture determination  	  8
        Crushing and sieving	  8
        Rock fragment determination	  8
        Soil homogenization  	  9
        Qualitative test for inorganic carbon	  9
        Bulk density determination	  9
        Sample shipment  	  9
        Record keeping	  10

     4  Quality Assurance/Quality Control  	  11

        Design components	  11
            Training   	  11
            Communications	  11
            Data quality objectives  	  11
            On-site systems audits	  12

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        Data evaluation	   12
            Quality assurance samples  	   13
            Method of estimating analytical precision	   13
            Precision results for rock fragment determination	   14
            Precision results for bulk density determination  	   14
            Completeness results  	   15

     5  Conclusions and Recommendations	   16

        General recommendations	   16
        Sample receipt 	   16
        Equipment Inventory	   16
        Sample drying	   17
        Moisture determination  	   17
        Soil homogenization  	   17
        Rock fragment determination	   17
        Qualitative test for inorganic carbon	   17
        Bulk density determination	   18
        Sample shipment   	   18
        Quality assurance and quality control  samples	   18
        Record keeping	   19
        Design components	   19

References	   24

Appendix A  Preparation Laboratory Manual for the
            Direct/Delayed Response Project  	   25

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                                     Figures
Number                                                                        Page

   1     Form 101 - Master data form  	  3
   2     Form 102 - Shipping form	  4
   3     Sample receipt form	20
   4     Bulk density raw data form  	  21
   5     Bulk sample processing form	22

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                                       Tables
Number                                                                          Page

   1  Precision estimates for rock fragments	  14
   2  Precision estimates for bulk density	  14

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                                Acknowledgments


     Critical peer reviews by the following individuals are gratefully acknowledged: W. Banwart,
University of Illinois, Urbana, Illinois; and J. S. Lohse, Illinois Department of Agriculture, Bureau
of Farmland Protection, Springfield, Illinois.

     The following individuals provided guidance in the development of statistical analyses:
T. Starks,  Environmental Research Center, University of Nevada, Las Vegas, Nevada; and
J. E. Teberg and M. J.  Miah, Lockheed Engineering  & Sciences Company, Las Vegas, Nevada.

     Critical reviews by  the following individuals  were instrumental  in the preparation of this
document and are gratefully acknowledged: C. J. Palmer, Environmental Research Center, University
of Nevada, Las Vegas, Nevada;  J. C. Foss, University of Tennessee, Knoxville, Tennessee;  B. R.
Smith,  Clemson University,  Clemson, South Carolina;  J.  J. Lee, U.S. Environmental  Protection
Agency, Environmental Research Laboratory, Corvallis, Oregon; D. S. Coffey, Northrop Services, Inc.,
Corvallis, Oregon; and J. K. Bartz, M. D. Best, G. E. Byers, W. H. Cole, and M. L Papp, Lockheed
Engineering & Sciences Company, Las  Vegas,  Nevada.

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                                       Section  1

                                     Introduction
Overview

     The U.S. Environmental Protection Agency
(EPA),  in conjunction  with the  National Acid
Precipitation Assessment Program  (NAPAP),
has  designed and  implemented  a  research
program to predict the long-term response of
watersheds and surface waters in the United
States to acidic deposition.  Based on  this
research, each watershed system studied will
be classified according to  the  time  scale in
which  it will reach an acidic  steady  state,
assuming current levels of acidic deposition.
The  Direct/Delayed Response Project (DORP)
was designed as the terrestrial complement to
the aquatic resources program.

     As part of the DORP, the services of two
preparation laboratories were obtained through
interagency agreements to receive and process
soil samples collected from the  Southern Blue
Ridge Province (SBRP) of the  United States
and  to perform preliminary analyses on these
samples.  Laboratories located  at the Univer-
sity of Tennessee in Knoxyille, Tennessee and
at  Clemson University  in  Clemson,  South
Carolina were selected for  these tasks be-
cause of the proximity of each laboratory to
the sampling sites and analytical experience
with soils of the region.

     Each  laboratory  was supervised by a
university faculty member and a laboratory
manager.  The manager was responsible for
ensuring that the integrity of the soil samples
was maintained after the samples were deliv-
ered to  the preparation  laboratory.   Both
laboratory managers had received university
degrees in soil science and the other labora-
tory  personnel had  received prior training in
soil science. All participants were required to
comply with specified protocols, as outlined in
Appendix A.

     Soils processed at the preparation labo-
ratories were  collected from sampling sites
located  in  Georgia, South Carolina,  North
Carolina,  and Tennessee and  from  special
interest watersheds in North  Carolina  and
Virginia.   Upon receipt of bulk soil samples
and clod samples from the sampling crews,
laboratory personnel performed the following
analyses on the samples:

     •  Moisture  determination (air-dry mois-
        ture content)

     •  Rock  fragment determination  (2- to
        4.75-millimeter and 4.75- to 20-milli-
        meter fractions by
        weight)

     •  Qualitative test for inorganic carbon

     •  Bulk density  determination  by clod
        analysis

     Laboratory personnel prepared analytical
samples derived  from homogenized,  air-dry
bulk  samples.  The analytical samples were
labeled and were  organized according to their
parent pedons. Multiple batches were assem-
bled, each containing no more than 37 routine
and duplicate samples, two natural audit pairs,
and a preparation duplicate.  The  duplicates
and audit pairs were included in each batch
for quality assurance  (QA) purposes.   The
samples were randomized within each batch
by the laboratory  manager.  The assembled
batches  were shipped to  various analytical
laboratories contracted by EPA for additional
analyses.

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     The preparation  laboratories  were  re-
sponsible for completing Form 101 (see Figure
1) for each batch of samples.  This data form
contained the results of all analyses performed
on  the  soil samples  by preparation  labora-
tories prepared a shipping form, Form 102 (see
Figure 2), that was included with each batch
of samples shipped to the analytical  labora-
tories.    The shipping form  identified  each
sample by a batch and sample number accom-
panied by a mineral or organic soil designa-
tion. This procedure disguised the originating
pedon and horizon  of each field sample,  as
well as the identity of the QA samples.

     All  information,  e.g.,  sample  labels,
received  from the  sampling  crews and raw
data from the preparation laboratory analyses
were documented in log books. The protocols
specified that completed log books were to be
sent to  EMSL-LV QA staff for use during the
data verification  process.

     QA and quality control  (QC) measures
were applied to  maintain consistency in soil
preparation  protocols and  to ensure that the
soil sample analyses would yield results of
known quality.  Laboratory personnel received
training in the preparation procedures  and
analytical  methods.  QA representatives from
EMSL-LV and  ERL-C conducted on-site sys-
tems  audits of the preparation laboratories.
Weekly communication between the QA staff
and laboratory personnel was established to
identify, discuss, and resolve issues.

Objectives

     This document reports the results of the
preparation  laboratory  operations  and QA
program for the SBRP Soil Survey.  Information
concerning the specified protocols  for the
preparation  laboratories can  be found in
Appendix A.

     The  following sections contain detailed
information concerning the preparation labora-
tory methods, operations, and data quality. A
series of recommendations for improving both
the quality and efficiency of  preparation labo-
ratories in  future  DDRP  soil  surveys  are
included.

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                             NATIONAL ACID DEPOSITION SOIL SURVEY (NADSS)
                                               FORM 101


                                                             DATE RECEIVED
                                                             BY DATA MGT.	
                                                                        O  O  M M  M  V  ¥

Set ID
Data Sa
Dale RE
Dale Pr
No. ol S
SAMPLE
NO.
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
13
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
Balr.h ID
CrpwID
Prop 1 ah ID
1 an Sel Snnl To
Dale Shinned


Cnived
pp Cnmptplpd
amoles ._ .__
sire 10










































Signature ol Preparation
Comments:
SAMPLE CODE










































SET
ID










































COARSE
FRAGMENTS
%
CF










































AID DRIED
MOISTURE
S
W H50




















































































INORO.
CARBON
(1C)
1* fES
N ' NO









































BULK
DENSITY
VCC










































ahnr.ilnry Manarjnr'

                                                               COLO - (»t. c
Figure 1.  Form 101 - Master data form.

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                             NATIONAL ACID DEPOSITION SOIL SURVEY (NADSS)
                                           SHIPPING FORM 102
                                                           DATE RECEIVED
                                                           BY DATA MGT.
                                                                        ~
                                                                           U U M  V  V
O O M M U f V
Prop 1 .ih in Ham Rnrmvort
Batch ID , Data Shipped
Analylip.nl I ah in
SAMPLE NO.
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
10
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
AIR-OHIEO MOISTURE
•*
W USD






















































































Signature of Preparation Laboratory Manager:
Comments:
INORGANIC CARBON (1C)
T . ves
N » NO










































COARSE FRAGMENTS SHIPPED?
(CHECK T IF YES)












































Figure 2.  Form 102 - Shipping form.

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                                     Section 2

                Sample Preparation Methods and Analysis
     The  detailed  methods and  analytical
procedures used in soil preparation activities
for  the  SBRP  soil survey are given  in  the
protocols (Appendix A). Brief explanations of
the  specified methods and procedures  for the
preparation laboratory tasks are given  below,
including one correction to the protocols. The
procedures are discussed in sequential order
of performance by the preparation laboratories.

Sample  Drying

     Bulk samples are spread out on large
sheets of paper to air dry.  Where necessary,
several sheets of paper are placed underneath
the  samples to absorb excess moisture and
the  paper is replaced  periodically  for faster
drying. Laboratory personnel occasionally stir
the  samples to encourage uniform drying.

Moisture Determination

     A  15- to  20-gram air-dry  subsample is
placed in a drying dish and is weighed.  The
dish is placed in a drying oven for a minimum
of 16  hours, 105  *C for mineral samples and
60  "C for organic samples.  The  sample is
allowed  to cool in a desiccator for 30 minutes
and is reweighed. This procedure is repeated
until the difference between successive daily
moisture contents is less  than 2.5 percent.
The final air-dry moisture content is recorded.
(Note:   Field moisture was not a  measured
parameter for the SBRP survey.)

Crushing and Sieving

     After recording the weight of  the air-dry
bulk sample, the soil  peds  are crushed  to
allow  passage of the less than 2-mm soil
fraction  through  a No. 10 sieve.  A wooden
rolling pin or a rubber stopper is used to crush
the peds,  depending on the consistence  of
rock fragments in each sample.
Rock Fragment  Determination

     Rock  fragments  remaining  from  the
sieving procedure are retained on either one of
two sieves.  Fragments retained on the No. 4
sieve  constitute  the 4.75- to 20- millimeter
coarse pebble fraction (fragments larger than
20 millimeters in diameter were sieved by the
sampling crews).  Fragments retained on the
No. 10 sieve constitute the 2.0- to 4.75-milli-
meter fine pebble fraction. Gravimetric analy-
sis is used  to determine the percentage  by
weight of each fraction in the soil samples.

Soil  Homogenization

     A Jones-type riffle splitter is used for
homogenizing the  samples.  The less than 2-
millimeter fraction is deposited evenly across
the baffles of the riffle splitter and is  chan-
neled  into two receiving pans.  After  seven
passes through the riffle splitter, the  entire
sample is combined for a final pass through
the riffle splitter.   The material in one pan is
placed into a plastic sample bag for archiving,
and the  material  in  the other  pan repeatedly
passes through the riffle splitter until a one-
kilogram subsample is obtained.

Qualitative Test for Inorganic
Carbon

     One gram of air-dry soil is placed  in the
well of a  porcelain  spot plate,  is saturated
with deionized water, and is stirred to release
any entrapped air.  The sample is observed
through  a microscope or a  stereoscope in
order to detect an effervescent reaction when
three drops of 4N HCI  are added. Two types

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of QC samples are used to determine the
detection limit and to qualitatively calibrate the
test.

Bulk Density Determination

     Replicate  soil clods, usually three per
horizon, are collected by the  sampling crews
(Blume et al., 1987).  Initially, the clods are
weighed at the laboratory and are dipped in a
1:7 saran:acetone mixture.   The  clods are
suspended from  a line, are  allowed to dry
briefly, and are reweighed. The dipping proce-
dure is repeated until each clod is assumed to
be impervious to water.

     Approximately 800  milliliters of deionized
water in  a one-liter beaker is de-gassed by
boiling, is allowed to  cool to room tempera-
ture, and is tared on a balance.  Each clod is
submerged in the water and the increase in
weight is recorded.  The clods are oven-dried
for 48 hours, cooled, and  reweighed.  A two-
hour heat treatment in a  400 *C muffle furnace
allows the saran to vaporize, and the clods are
cooled and again are reweighed.  Each clod is
crushed and is passed through a 2- millimeter
sieve to determine percent by weight of rock
fragments. This figure  is used to adjust the
bulk  density calculation  for  rock fragment
content.

     Bulk density is defined as the  mass of
dry soil per unit volume,  including pore space,
and expressed as grams per cubic centimeter
(g/cm3). Bulk density normally ranges from 1.0
to 1.8 g/cm3 in mineral soils (USDA-SCS, 1983).

      Laboratory  personnel at  the Clemson
preparation laboratory discovered that one of
the bulk density algorithms was  given incor-
rectly in the protocols. The algorithm used to
estimate the  air-dry saran weight was  origi-
nally written as:
     MTS =
            X (M. -
              a - 1

where:  MTS = air-dry saran weight

          X = total number of coatings (field
              and laboratory)

         Ma = clod weight after final coating

         M, = initial   clod   weight   after
              unpacking

          a = number of laboratory coatings

     The correct algorithm  is as follows:

            X (M. - MO
     MTS =
                 a
     All  participants  were  informed of the
error as  soon  as it  was discovered.   The
laboratory data forms immediately were amen-
ded to show the corrected values.
                                            6

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                                       Section 3
                      Preparation Laboratory Operations
     This section describes preparation labo-
ratory operations, including difficulties with the
procedures and deviations from the protocols.
The laboratories are characterized as Labora-
tory A and Laboratory B to  prevent disclosure
of their identity, except where necessary to
clarify an activity.

Sample Receipt and  Storage

     Due to budgeting and logistical difficul-
ties, neither preparation laboratory was admin-
istratively operational when sampling began.
The laboratory director at Laboratory B retired
from the position soon after preparation activ-
ities were initiated, causing  some initial confu-
sion with sample tracking and processing.

     Each laboratory provided the sampling
crews with convenient access to cold storage.
A sample receipt log book  was kept at each
facility to  allow sampling crews to log  in the
samples.  Each laboratory was responsible for
checking that all  samples delivered by  the
sampling crews were recorded in the log book.
Entries  were  checked  for  legibility  and
accuracy.

     The temperature of the storage facilities
was maintained at the contract-specified 4 *C,
with one exception. Laboratory B had a tem-
porary  refrigeration failure that was reported
to the QA staff immediately. The refrigeration
unit was  repaired  within  approximately  six
hours, and the highest temperature measured
during  the failure was 14 °C.  The lapse in
cooling may have had some effect on micro-
bial activity in field-moist samples stored  at
the  facility, although studies were not con-
ducted to  identify this effect.  Analytical data
for the affected samples processed  at Labora-
tory B will be flagged in the verified data base,
denoting possible  contamination.    If time
permits,  the data  will  be evaluated during
verification to determine whether or not there
are suspect values that indicate contamination
may have occurred.  Although the effects are
expected to be negligible, organic transforma-
tions involving carbon, nitrogen, or sulfur may
have occurred. This issue will be discussed in
the QA report for the analytical data.

     In order to provide an equal distribution
of  incoming samples  and  to improve  the
efficiency of available cold storage and labor,
34 bulk samples and 72 corresponding clods
were transferred  from the University of Ten-
nessee to Clemson University.  The samples
were packed in coolers and were transported
by truck.  The  samples were returned to cold
storage   within eight hours.   This  transfer
provided each laboratory with approximately
400 bulk samples and their respective clods.

     There  was some confusion concerning
the proper dispensation of practice samples
that were delivered  to Laboratory  B at  the
request of  the  laboratory director.   These
practice samples had been collected by one of
the sampling crews in preparation for routine
sampling.   The  samples were delivered  to
Laboratory B and were logged into the sample
receipt log  book.   The  samples  were  not
identified as practice samples, therefore labor-
atory personnel treated the samples as if they
were routine samples  and processed them
accordingly.  The error was discovered after
the samples had undergone  soil analysis at
the analytical laboratories. Data for the prac-
tice samples were later removed from the data
base.

Equipment Inventory

     The laboratory managers were respon-
sible for tracking the distribution of equipment

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to the  sampling crews.   Each preparation
laboratory stored the equipment in a locked
room with limited access. The sampling crews
usually obtained supplies while samples were
being delivered  to the cold storage facility.
Laboratory managers generally were notified in
advance of a sampling crew's arrival to ensure
that the crews had access to the supply room.
The sampling crews were asked to record in
the equipment log book all supplies taken.

     A  complete  inventory was  performed
monthly at each preparation  laboratory. Equip-
ment shortages were  reported  to EMSL-LV
during the weekly conference call. Laboratory
personnel were tasked  with  providing the
saran and acetone used  in  mixing  a  solution
for coating clods in the field.  They also were
responsible for providing gel packs used in the
refrigeration  of bulk samples during transport.

     It was decided at the training workshop
that  certain  sampling hardware  would  be
distributed to the sampling crews via the Soil
Conservation  Service  (SCS)  state  offices
instead of the preparation laboratories.  After
sampling  was  completed,   difficulties  were
encountered  in tracking  and recovering  this
equipment because the laboratory  managers
were not  provided with  a  master inventory
sheet listing all equipment  provided  to the
crews.   Additional  difficulties occurred when
sampling  crews utilized both  preparation
laboratories  as  supply points.

     After the soil  preparation activities were
completed, leftover supplies were inventoried
and were sent to EMSL-LV for storage. Cam-
eras  used to photograph the sampling sites
were turned  over to the SCS state  offices by
some of the sampling crews. Although there
were instances of  misplaced sampling hard-
ware, most of the  equipment eventually was
located. A complete list of the types of equip-
ment supplied  to  the crews is  provided  in
Appendix A.

Sample Drying

     Although there were no deviations from
the specified  protocols  for sample drying,
concerns were raised about air-drying the soils
during humid or rainy weather.  Drying areas
for both laboratories were located in buildings
lacking humidity control:  one used a green-
house and the  other used a prefabricated
metal structure. Samples occasionally took as
long as three weeks to dry.  Long-term expo-
sure of the samples during  humid weather
provided a greater opportunity for contamina-
tion.  Both  laboratories loosely covered the
drying  samples  with kraft paper  to  reduce
airborne contamination.

Moisture Determination

     One  significant deviation from the speci-
fied protocols for the air-dry  moisture deter-
mination occurred.  Laboratory  B obtained a
convection oven  after the sample processing
had begun.  Therefore, the initial air-dry mois-
ture  determinations  at this  laboratory were
made by  an alternate method approved in
advance by  QA staff.  The alternate method
was to weigh a known quantity of sample and
allow it to  dry overnight under the same condi-
tions as the bulk sample.  The sample then
was reweighed.   If the change in sample
weight was less than 2.5 percent absolute
over a two-day period, it was presumed that
the soil  was ready for processing.  If not, the
procedure  was repeated until  the variation in
weight was  less  than 2.5 percent.

Crushing and  Sieving

     There were  no  deviations from the speci-
fied protocols for sample crushing and sieving.
Laboratory A generally used  the rolling pin
method. Because of the soft, weathered state
of rock fragments in its samples, Laboratory B
generally used the specified alternate method,
which utilized a rubber stopper to crush indivi-
dual  soil peds.  This procedure allowed the
passage of  soil  through the  sieves without
disturbing  the fragments.   The  rolling  pin
method  occasionally was used by Laboratory
B for those samples  containing hardened peds
or few fragments, and a notation of this was
made in the  sample  processing log book.

Rock  Fragment Determination

     There were  no  deviations from the speci-
fied protocols for rock fragment determination.
Laboratory B washed all rock  fragments in
deionized water to remove adhered soil before
calculating the percentages. Both laboratories
bagged  and  labeled  the  fragments  and
awaited further instructions for shipment.
                                           8

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 Soil  Homogenization

      There were no deviations from the speci-
 fied protocols for soil homogenization. During
 October, 1986 it was discovered that there was
 insufficient audit material remaining to  con-
 tinue processing one-kilogram audit samples.
 As a result, the protocols were modified and
 the laboratory managers were advised to begin
 preparing 500-gram analytical samples instead
 of one-kilogram samples. All batches shipped
 from  Laboratory A contained 500-gram sam-
 ples.   Because many of the batches from
 Laboratory B already had been shipped, only 5
 of the 14 total  batches  at Laboratory B con-
 tained 500-gram samples.

      Both laboratory managers voiced concern
 about rehomogenizing the bulk samples  to
 obtain subsamples for  mineralogical study.
 Repetitious  soil homogenization  could  mis-
 represent the particle-size distribution because
 of the potential for loss of clay and fine silt
 particles during riffle-splitting.   The  list  of
 samples selected  for mineralogical analysis
 was sent to the preparation laboratories after
 soil  processing was  well underway.   Bulk
 samples had to  be retrieved from storage,
 rehomogenized,  subsampled, relabeled,  and
 returned to storage.   This exercise  was very
 time consuming and might have been avoided
 through better planning and communication.

 Qualitative Test  for Inorganic
 Carbon

      There were no deviations from the speci-
 fied protocols for  the inorganic carbon test.
 Inorganic carbon  was  not  detected in any
 samples collected.

 Bulk Density Determination

     There were no deviations from the speci-
fied protocols for the bulk density determina-
tion.  Clod analysis was chosen as the meth-
od for determining  bulk density, despite a few
disadvantages.  Obtaining replicate clods from
dry, loose,  or extremely wet soils and from
horizons containing many rock fragments often
can be difficult or impossible. Another concern
is  that the bulk density values that are ob-
tained may be higher  than the  average bulk
density  of  the  soil horizon they represent,
because sampling could be biased toward the
collection of firmer, more coherent clods cap-
able of withstanding disturbance during sam-
pling and transport.

     Variations in bulk density measurements
could occur when clods are allowed to air dry
after multiple  saran coatings.  Because the
saran  is permeable to water vapor, the clod
weight  could  be affected  by moisture  loss
from prolonged  drying.   This situation did
occur at Laboratory A during the early stages
of  sample processing,  although  the actual
number of affected clods is unknown.  Thirty-
nine clods at Laboratory B  were discarded
because a weak coating  solution  used in the
field rendered the clods unsuitable  for analysis
upon arrival at the laboratory.

     According to the log books, three floating
clods were identified. Each clod was forcibly
submerged to  allow a bulk density determina-
tion to be made.

Sample Shipment

     The preparation laboratories were provi-
ded with shipping materials used  for packag-
ing  the  samples and  with a  express  mail
charge number for overnight shipment of the
samples to the analytical  laboratories.  Labor-
atory personnel were instructed to assemble
batches  containing as many as  37  routine
samples and field duplicates.  Each batch also
contained one preparation duplicate prepared
by  the  laboratory and two  pairs of  natural
audit samples provided by QA staff at EMSL-
LV. The laboratory managers were  responsible
for randomizing the samples within each batch
and assigning  sample numbers. The individual
samples were tagged with the  appropriate
label B and were packed in cardboard boxes
for  shipment  to the designated analytical
laboratory.

     QA representatives routinely called one or
two days in advance to notify the  preparation
laboratory manager that a shipment was due
for delivery to an analytical laboratory.  Labor-
atory B expressed some  dissatisfaction  with
the amount of advance notice received.  In a
few  cases, notification  was given  the  day
before  batches were to be shipped. Labora-
tory A was not directly affected because their
batches  generally  were  sent  in  two mass
shipments.

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     Because  of  insufficient detail  in  the
protocols, there was  some confusion in the
handling of the audit  samples.  Later  written
instructions  stated that the audit samples
should be identical in  appearance to the rou-
tine samples, although the audit samples had
arrived  at the  preparation laboratories  with
numbers on both the  outer canvas bags and
inner plastic  bags.   The  integrity and  ano-
nymity of the audit samples were jeopardized
because Laboratory A  left the audit samples in
their original bags and Laboratory B re-bagged
the audit samples.

Record Keeping

     Both  preparation  laboratories   were
provided with log books to use for recording
data. Each laboratory manager was instructed
to organize log books containing the following
information:

     •  Label A -  This log  book contained
        labels that originally were filled out by
        the sampling  crews and were  affixed
        to the inner bag of the bulk samples.
        Laboratory B  placed  these labels on
        looseleaf paper and  organized them
        into a binder.  Laboratory A did not
        submit their labels, and later  efforts
        to locate them were unsuccessful.

     •  Clod  Label -  This log book contained
        labels  that were  filled  out by  the
        sampling crews and affixed  to the
        prepared clods. Laboratory A did not
        submit their labels, and later  efforts
        to locate them were unsuccessful.
     •  Sample Receipt -  This log book was
        filled out by the sampling crews upon
        delivery   of    samples   to  each
        laboratory.

     •  Equipment -    The  sampling  crews
        were asked to  list the field  supplies
        they obtained at the laboratories.  The
        laboratory managers were responsible
        for tracking and confirming the equip-
        ment inventories.

     •  Percent Moisture  -    This log book
        contained  raw data from the air-dry
        moisture analyses.

     •  Percent Rock Fragments -   This log
        book contained raw  data from  the
        rock fragment analyses.

     •  Bulk Density  -  This  log book con-
        tained raw data from the bulk density
        analyses.

     •  Inorganic  Carbon -   This log book
        contained  raw data from the test for
        inorganic carbon.

     •  Sample Processing -  This log book
        tracked the progress of the soil sam-
        ples through  the various preparation
        activities.

     Because a standard format for each log
book was not specified, there was variation
between the laboratories. As a result, verifica-
tion of  the  data took more time than was
expected.    Laboratory  A assigned  internal
laboratory numbers to their samples, making
it difficult  for QA  personnel to match these
numbers to the  original sample codes.
                                           10

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                                      Section 4

                      Quality Assurance/Quality Control
     A  specified QA/QC program must be
followed during the course of survey activities
to ensure that the resulting data are of known
quality.  The QA/QC program for the SBRP soil
survey consisted of design  and  evaluative
components that aided survey participants in
obtaining samples and  producing  data that
meet the needs of end users.

     The QA/QC design for the preparation
laboratories included training personnel in the
protocols to be followed, establishing a com-
munications network, assessing data quality,
and performing on-site systems audits.  The
data  were  evaluated   systematically  using
analytical data from the clod  replicates and
from  the  QA duplicate  samples that were
included in each batch of  routine samples.
The following sections explain  aspects of the
QA/QC  program  in  relation  to preparation
laboratory activities.

Design Components

Training

     Preparation laboratory   personnel  at-
tended a regional workshop held in Knoxville,
Tennessee, from March 18 through 20, 1986.
The purpose  of the workshop was to review
the laboratory protocols and discuss key
activities.  Training of the participants estab-
lished a basis for consistency between the
laboratories, thereby increasing the likelihood
that the data would be of comparable quality.

Communications

     Weekly conference calls  assisted  in
keeping the preparation laboratories operating
efficiently  and  consistently  by  providing  a
forum that  allowed potential difficulties to be
identified, discussed, and resolved.  Prepara-
tion laboratory managers, QA personnel, and
scientists involved  in the study of soil miner-
alogy participated in these  calls.   Issues
discussed during the conference calls included
supply shortages and clarification of proce-
dures, e.g., sample labeling, record keeping,
and drying of clods.  The laboratory manager
at Laboratory A stated that  the conference
calls were not as beneficial as routine calls for
dealing with specific issues.

Data Quality Objectives

     Data quality objectives for  the prepara-
tion laboratories were not established during
the SBRP soil survey. The preparation labora-
tories were assessed according to the follow-
ing data characteristics:

     •  Precision and accuracy  - These are
        quantitative measurements  that esti-
        mate the  amount of  variability and
        bias inherent in a  given  data set.
        Precision refers to the level  of agree-
        ment among repeated measurements
        of  the same parameter.   Accuracy
        refers to the difference  between an
        estimate  based on  the   analytical
        results  and the true value of  the
        parameter being measured.

     •  Representativeness - This  refers  to
        the degree to which the collected data
        accurately reflect the population  or
        medium that is  sampled.

     •  Completeness  - This refers to  the
        amount of data that is  successfully
        collected with respect to the amount
        intended in the design.  A defined
        percentage of the  intended amount
        must be  successfully collected for
                                           11

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        conclusions based on the data to be
        valid.   Lack  of  data completeness
        may reduce  the  precision of  esti-
        mates, may introduce bias, and may
        reduce the level of confidence in the
        conclusions.

     •  Comparability -  This refers to  the
        similarity  of   data  from  different
        sources included in a single data set.
        If more than  one laboratory is  ana-
        lyzing samples,  uniform  procedures
        must be used to ensure that the data
        from different sources are based on
        measurements    of  the  same
        parameter.

     These  five data  quality characteristics
were identified in the DDRP QA Plan, and their
application to preparation laboratory activities
were stated (Bartz et  al., 1987).  A brief des-
cription of the specific characteristics follows:

     •  Precision and  Accuracy - The prepara-
        tion laboratory combines sets of field
        samples  into  one batch containing  a
        maximum of 39 routine and duplicate
        samples. After processing, i. e., air
        drying, crushing, sieving,   and   ho-
        mogenization, one bulk sample is split
        into two subsamples which are term-
        ed preparation duplicates.  Compari-
        son of physical and chemical data for
        these duplicates  allows evaluation of
        the  subsampling  procedure.

     •  Representativeness - Each bulk sam-
        ple  is  processed  by a preparation
        laboratory to  obtain  a homogeneous
        sample.  Homogenization is accomp-
        lished by passing the sample through
        a Jones-type  riffle  splitter at least
        seven times.  The riffle splitter also is
        used for subsampling.  All samples
        not  being processed are stored at  4
        °C by the preparation laboratory.

     •  Completeness - Each batch of sam-
        ples sent to  a contractor  analytical
        laboratory includes  the preparation
        duplicates.

     •  Comparability - All preparation labora-
        tories process bulk  samples  accor-
        ding to the protocols.  Strict  adher-
        ence  to  protocols  should  result in
        comparability   among   preparation
        laboratories.

     Precision is estimated in this QA report
by evaluating  field  duplicate data  from the
rock fragment  analyses and  replicate data
from the bulk density analyses.   Additional
precision estimates using analytical data from
the field duplicates and from the  preparation
duplicates will be documented in the QA report
on the  analytical laboratory data.

     Accuracy cannot be assessed because:
(1) true values for the parameters in question
are not known,  (2) quality control calibration
samples were not used in the determination of
bulk density,   (3) it was not known how to
provide quality control calibration  samples to
evaluate the rock fragment analyses, and (4)
it was  not known how to provide audit sam-
ples for the rock fragment and bulk density
analyses.  Relative accuracy  based upon an
interlaboratory study will be addressed in the
QA report on the analytical laboratory data.

     Representativeness will be addressed in
the QA report on the analytical data by using
data from the preparation duplicates  to as-
sess the subsampling procedure performed by
each laboratory.

     Completeness  is  measured  by  each
laboratory's performance of the analyses and
processing tasks for all samples assigned.

     Comparability  is  evaluated  using the
precision data  from preparation  duplicates.
This evaluation will be documented in the QA
report on the analytical laboratory data.

On-Site Systems Audits

     Pre-sample  audits of both  preparation
laboratories were conducted during the Spring
of 1986.  These visits  were  designed  to as-
sess the laboratory facilities, equipment, and
staff before any samples were  received or
processed.  Laboratory A was audited by a
QA representative from EMSL-LV, and Labora-
tory B was  audited  by a QA representative
from ERL-C.

     Laboratories A and B later were audited
by a QA representative from EMSL-LV in June,
1986.   At Laboratory A, the  QA  auditor ob-
served sample drying and  toured the cold
                                            12

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 storage and laboratory facilities. At Laborato-
 ry B, the auditor observed the early stages of
 sample  preparation,  including  the  sample
 drying, sample crushing, and soil homogeniza-
 tion procedures.

      Laboratory A had not been covering their
 drying samples with paper, thereby leaving the
 samples vulnerable to airborne contamination.
 The laboratory manager  was  instructed to
 loosely cover all samples in the future. Labor-
 atory B was not  calibrating the thermometer
 used for recording  the  temperature of the
 water in bulk density calculations. The labora-
 tory manager was instructed  to  check the
 accuracy of the thermometer at least once a
 month.  It also was discovered that Labora-
 tories A and B did not have the required Class
 S  weights  for  calibration  of  the  balance.
 These   weights   were   obtained   shortly
 thereafter.

     The log books were inspected by the QA
 auditor, who  observed  pencil entries in the
 sample receipt log book at Laboratory B.  To
 correct this deficiency, a  black pen was at-
 tached to the log book and was used there-
 after by  the  sampling crews.  Laboratory A
 occasionally  used blue  ink  instead  of the
 specified black ink. Although both laboratories
 set up their log books with different formats
 and headings, the books contained all required
 data.

 Data Evaluation

 Quality Assurance Samples

     Three types of  QA samples were  in-
 cluded in each batch of samples submitted to
 the analytical laboratory:   (1)  field duplicates,
 (2)  preparation duplicates,  and (3)  natural
 audit samples. Data from the QA samples will
 be evaluated in the QA report for the analytical
 laboratory data.  An explanation of each type
 of QA sample follows.

     One horizon per sampling  crew per day
 was sampled in duplicate  as specified in the
field protocols (Blume et al., 1987).  The first
sample of the pair is considered the  routine
sample, and the second sample is referred to
as  the field  duplicate.   The field  duplicate
underwent the same preparation steps as its
associated  routine sample.  This allows an
estimate to be made of the combined effects
of  sampling  error,  horizon variability,  and
preparation laboratory error.

      One sample per  batch was chosen by
the laboratory manager to be processed and
then split into two subsamples.  On the Form
101 sent to EMSL-LV, one of the pair retained
the routine  sample code  and the other was
assigned the preparation duplicate designa-
tion.   Analytical  data  from  the preparation
duplicates allow  the  range of  physical and
chemical characteristics for splits of the sam-
ple material to be  determined.  Statistical
analyses of the data will allow an estimate to
be made of the within-laboratory variability due
to subsampling.

      Two natural  audit pairs supplied  by QA
staff  were included in each  batch that was
sent  from  a preparation laboratory  to  an
analytical laboratory, but the samples did not
undergo any processing  at  the preparation
laboratory.   These samples  were used to
assess  the  performance  of the  analytical
laboratories.  Specific  information on  audit
samples can be found in Bartz et al. (1987).

Method of Estimating Analytical
Precision

      Data for  the rock fragment and bulk
density determinations were grouped by labor-
atory into data sets.  A scatter plot of horizon
standard deviation versus horizon mean was
generated to evaluate the relationship between
precision and concentration. The  data for both
parameters  displayed  a random  pattern of
standard  deviation, indicating that precision
was independent of concentration.  On  this
basis, a completely randomized design  model
was selected for the statistical estimation of
precision (Steel and Torrie, 1960).  The  model
that represents data collected at a specific
sampling  site  can  be  demonstrated, as
follows:

     y,, = u + h, + ey

where:  yN = the variable of interest for the jth
             observation from the ith horizon
             represented

         u = the   general  mean  of   the
             population
                                           13

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        h, = the effect of the ith horizon on
             the variable of interest

        By = the random error of analytical
             measurement for the jth observa-
             tion  from   the  ith   horizon
             represented

     The  model was used to perform statis-
tical analyses of  (1)  rock fragment data from
the field duplicates and (2) bulk density data
from the replicate clods. A root mean square
error statistic was used to estimate the pooled
standard deviation (Sp) across all pedons and
horizons for each laboratory data set, and the
coefficient of variation (CV)  was derived by
dividing Sp  by  the mean of the data set (x)
and multiplying by 100.

Precision Results for Rock Fragment
Determination

     Field duplicate data for the rock fragment
determination were analyzed by the completely
randomized design model to provide overall Sp
and CV values for each preparation laboratory.
Summary  statistics incorporating these values
are provided in  Table 1.
                                     Because of the simplicity of the method
                                used for determining  the  percentage of rock
                                fragments in the bulk soil samples, a greater
                                amount of the imprecision can be attributed to
                                spatial horizon variability or sampling bias and
                                a  lesser amount  to  preparation laboratory
                                bias.  The field sampling  imprecision may  be
                                an indication of within-horizon rock fragment
                                variability or improper field duplicate sampling
                                technique.

                                Precision Results for Bulk Density
                                Determination

                                     Data from the bulk density determination
                                were analyzed by the completely randomized
                                design  model to provide  overall Sp  and CV
                                values  for the sets  of replicate clods at each
                                preparation laboratory. In addition, CV values
                                were generated for two  data groups  repre-
                                senting the sets of clods which exhibited a
                                mean bulk density that was either greater than
                                or less than the mean  bulk density  of  each
                                laboratory's clods. Summary statistics for the
                                Sp and CV values are given in Table 2.

                                     The CV values less than and greater than
                                the mean were evaluated in order to determine
Table 1.  Precision Estimate* for Rock Fragments
Laboratory
     Field Duplicates
     Number of Pairs
              Rock Fragments
              Mean (percent)
                       Sp
                             CV
    A

    B
           43

           61
                   7.1

                  13.6
                      1.371

                      1.673
                           19.33

                           12.32
Table 2.  Precision Estimates for Bulk Density
Laboratory
Number of
Horizons
Bulk Density
Mean (g/cm1)
 Sp
  CV
CV (x)
    A

    B
  262

  267
   1.28

   1.27
0.159

0.118
12.47

 9.30
21.09

12.82
 7.77

 7.18
                                             14

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whether or not the statistical relationship of
higher CV values at lower concentrations,  in
this case at lower bulk densities, would hold
true  for bulk density data.  The  CV  values
presented in  Table 2 appear to confirm this
relationship.

      The Sp values suggest a consistency of
bulk  density  values within a given horizon.
Audit  reports  indicated that the  sampling
crews were  able to choose representative
clods from each horizon and that the labora-
tories were consistent in their use of measure-
ment techniques.  However, the exact percent-
age of error contributed to the Sp values by
horizon variability, sampling bias, or laboratory
imprecision cannot be determined because (1)
inherent spatial variability made  it impossible
to sample identical field clods or  to provide an
audit sample  for  measurement of potential
sampling bias, and  (2) the preparation labora-
tories  were not provided with audit samples
to allow estimation of laboratory bias.

      The following types of  sampling errors
could contribute to sampling bias for the bulk
density replicates:

      • Collection of replicates from  transi-
        tional zones or adjacent horizons

      • Mislabeling of clods

      • Inconsistent saran coating procedure

      • Variability relating to the coherency of
        clods

      Based on the field experience of the SCS
sampling crews and the fact that the various
field  audit reports did not indicate major devia-
tions from the protocols, sampling bias is not
presumed to have  been a significant factor
affecting the Sp values.  Some variability in the
use of saran was mentioned in a few audit
reports, although the Sp values would not be
affected if the coating procedure was consis-
tent for all replicates within a horizon.

     Bias may be introduced at the prepara-
tion laboratory because of  measurement  or
method errors, such as  the following:

     • Transcription errors,  such  as  mis-
        recorded weights or sample codes

     • Inconsistent saran coating procedures

     • Improper clod handling, e.g., compac-
        tion

     • Incomplete drying

     • Loss of material during sieving

     • Incorrect numeric calculations

     • Faulty weights, e.g.,  clod  tags and
        hairnets  not  subtracted, or  balance
        not calibrated

     Because audit samples were  not provi-
ded, interlaboratory bias  could  not be  esti-
mated. Therefore, it is difficult to quantify the
potential effect of preparation laboratory bias
on the Sp and CV values.

Completeness Results

     The requested analyses and soil proces-
sing steps were performed on 100 percent  of
the bulk  samples and clods  received by the
preparation  laboratories.  This satisfied the
maximum theoretical  level of completeness.
Preparation duplicates were created for each
batch of samples sent to the analytical labora-
tories for a 100 percent level of completeness.
                                            15

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                                     Section 5

                     Conclusions and Recommendations
     The conclusions and recommendations
discussed below have been summarized from
information supplied by preparation laboratory
personnel, QA staff, and other survey partici-
pants.  The recommendations are presented
for consideration and possible implementation
in future surveys. Many of the recommenda-
tions are amendments to the  existing proto-
cols  and are based on  the information pro-
vided in Section 3.

General  Recommendations

     In future surveys, the preparation labora-
tories should be on-line and operational before
field  sampling begins.  This would allow an
opportunity to assess the overall preparation
function of  the laboratories and to clarify the
protocols  in advance  of  soil  processing
activities.

     The protocols should be  rewritten  to
include an  opening section that  addresses
general laboratory procedures.  The following
practices will help to improve laboratory safety
and ensure the integrity of the soil samples:

     •  It  should  be specified that  eating,
        drinking, and smoking is prohibited in
        the soil drying and processing areas.

     •  Inexpensive rubber or plastic gloves
        should be worn during all bulk sample
        processing activities.

     •  An  air-filtering  mask  or respirator
        should  be worn while homogenizing
        soils in order  to prevent excessive
        inhalation of  airborne soil particles.
     •  Samples should be crushed, sieved,
        and subsampled under an exhaust
        hood to limit airborne contamination.

     •  The saran  and acetone should  be
        mixed only  under an  operable fume
        hood.   A respirator also should  be
        worn.

Sample  Receipt

     Preparation laboratory personnel should
be  available  to  receive samples  from  the
sampling crews  and  to  check the  sample
labels against the log book entries.  If this is
not feasible, the check should be performed
the following day.  All discrepancies  should be
communicated to the QA manager within three
days. A computer spreadsheet should be kept
current,  showing the status of all samples
delivered to the laboratories.

     The delivery of practice  samples to a
preparation laboratory is not encouraged.  If
such  samples are  delivered,  the  laboratory
manager should  ensure  that the  practice
samples are separated from the routine sam-
ples.  Under no circumstances should practice
samples be logged into the sample receipt log
book.

Equipment  Inventory

     The preparation laboratories should  be
the sole distribution and recovery points for all
sampling equipment provided by EMSL-LV.  A
master inventory of equipment  should be kept
current and should  be  inspected by  the QA
auditor during the systems audits. The where-
abouts of missing equipment should be deter-
mined as quickly as possible.
                                          16

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Sample  Drying

     Implementation of the following modifica-
tions to the sample drying procedure could
expedite drying considerably:

     •  Stirring the samples every 24 hours
        would encourage rapid drying.

     •  In addition to the paper placed under-
        neath the samples, a  single sheet
        should be  placed  loosely over the
        samples.   The  paper  beneath the
        samples should be  replaced daily.

     •  Small,  clip-on,  multi-speed  electric
        fans can  be used to  facilitate  air
        movement in the drying area.  The
        fans should not  be allowed to blow
        directly on the samples.

Moisture  Determination

     Many participants  stated that a field
moisture determination would be very helpful
for correlating the  physical and  chemical
status of the soil at the time  of  sampling.
Three different methods for making this deter-
mination have been identified, as follows:

     (1)  Field moisture of clods: This method
would utilize the same clods sampled for bulk
density determination. To prevent evaporation,
clods would require greater  care in packaging
and refrigeration before being analyzed in the
laboratory.  A weight measurement would be
made for each clod upon  arrival at the labora-
tory, and would be used  to generate percent
field moisture values upon completion of the
bulk density analyses. Sampling crews would
identify  saturated  soil  horizons on  the field
data forms.

     (2)   Field  moisture of bulk samples:
Laboratory personnel would select  a repre-
sentative 20-gram mixed subsample from each
bulk sample upon its arrival at the laboratory.
The subsample would be placed in a capped
drying container prior to  weighing and oven-
drying.  Sampling crews  would  identify satu-
rated soil horizons on the field data forms.

     (3)  On-site  field moisture:   Sampling
crews would select replicate moisture samples
from each soil horizon sampled and place each
sample  in  a capped drying container.  The
samples would be weighed and oven-dried at
the preparation laboratory.  Saturated horizons
would be identified on the field data forms.

     Moisture data for saturated soils would
be tagged automatically in  the  data base,
irrespective of the method used to determine
field moisture. The gravitational water content
of a saturated sample is expected  to  vary
widely, depending on  the  soil  textural class,
length of storage,  and representativeness of
the bulk sample and subsample taken.

     Review  of the air-drying  procedure has
generated the following recommendation:

     •  When the laboratory manager believes
        that  a soil sample is air dry, 10-gram
        subsamples should  be analyzed for
        percent moisture on two successive
        days.
Soil Homogenization

     Both  laboratory  managers expressed
displeasure  with the amount of time  that
elapsed before a list of the soils chosen for
mineralogical study was provided. Every effort
should be  made to ensure that  this list is
provided to the preparation laboratories before
the analytical samples are split from the bulk
samples.  This would eliminate the  need for
laboratories to  locate  and homogenize  the
samples twice, thereby saving time and main-
taining sample integrity.

Rock Fragment Determination

     Dispensation  of  the  rock fragments
following analysis should be decided before
soil processing begins. This action will avoid
lengthy or costly storage of the fragments at
the preparation laboratories.

Qualitative  Test for Inorganic
Carbon

     Many participants  considered  the  inor-
ganic carbon test to be inadequate for identify-
ing the  soils  that  should undergo  further
analysis for carbonate. It has been suggested
that a pH determination in 0.1M CaCI2 on field-
moist  samples  would be  a better  way of
identifying those soils  likely to contain  inor-
ganic carbon  in  measurable concentrations.
                                           17

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This analysis also would provide valuable data
that cannot be  obtained  after the samples
have been air-dried.  A pH value of 6.0  or
higher is  a possible pH at which to target
individual  samples  for  further  analysis.   If
selected, this procedure should be performed
as soon as the samples arrive at the prepara-
tion laboratory.   The procedure  outlined  in
Cappo et al.,  1987 is recommended, except
that a field moist sample would be used.

Bulk Density Determination

     To avoid  some of the difficulties encoun-
tered with the bulk density determinations, the
following recommendations are made:

     •  Audit  samples  and  quality control
        calibration samples should be used
        during clod analysis (see recommen-
        dations under QA/QC samples).

     •  Clods should be air dry before being
        analyzed for bulk density. The air-dry
        state can be assumed when the clod
        weight  is  constant,  using  criteria
        similar to  those applied to the bulk
        samples.

     •  Clod  weights  should  be recorded
        immediately before coating with saran
        and  immediately   after  the  saran
        coating has dried in the laboratory.

     •  A  method  for  measuring the bulk
        density of floating clods should be
        added to  the   protocols.   Floating
        clods  should be identified on the bulk
        density raw data form and in the bulk
        density log book.

     •  The density of rock fragments within
        each  clod  should not always  be
        assumed to be 2.65  g/cm3 as sug-
        gested in the protocols.  In areas with
        a variety of lithologies or weathering
        characteristics, an appropriate low or
        high density value should be used
        where necessary.

Sample Shipping

     Both laboratory managers stated that a
shipping schedule would have helped to coor-
dinate labor and space requirements for sam-
ple  processing.  Laboratory personnel often
rushed  to  get  batches shipped because of
insufficient notification, usually one-day notice.
A tentative schedule should be in place before
the initiation of field sampling, and the sched-
ule should be finalized immediately following
the award of analytical laboratory contracts.

     All necessary shipping materials, e.g.,
forms and labels, should be delivered to each
preparation laboratory well in advance of the
first shipment  of batches to  an  analytical
laboratory. This will allow an opportunity to
review the forms and to resolve any issues
relating to the shipping  procedure or  the
sample packaging.  Information about  the
audit samples should be transmitted by EMSL-
LV at least one week before batch shipment,
which will allow the laboratory manager time
to assemble the batches and prepare Forms
101 and 102.   The Form 101  for each  batch
should be sent to  EMSL-LV on the  same  day
the batch is shipped.

Quality Assurance and Quality
Control  Samples

     Guidelines for the packaging of audit
samples should be better defined in the proto-
cols.  EMSL- LV should demonstrate the sam-
ple packaging procedure during the pre-sample
audit visit so that laboratory personnel do not
have to repackage audit samples.  To ensure
anonymity of the  samples at the  analytical
laboratories, preparation laboratory personnel
should  prepare the routine and  duplicate
samples to be indistinguishable from the audit
samples.

     Calibration samples should be utilized for
QC checks during the bulk density determina-
tion. It has been suggested that minerals of
known density, e.g.,  quartz  at 2.65 g/cm3,
would be appropriate. The analyses could be
monitored at regular intervals by using mineral
samples that compare favorably in size and
weight to the  clods.   While this  particular
technique  has not been tested at EMSL-LV,
calibrated mineral samples of the desired size
and density are readily available from labora-
tory supply outlets. The use  of graded sand
samples also has been suggested as  a  QC
check.

     A  synthetic  audit sample should  be
utilized to  estimate precision  and interlabora-
tory bias during the bulk density determination.
                                           18

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A set of plastic eggs that spans a wide range
of displacement capabilities  has been sug-
gested as an  audit medium,  although  proto-
types of synthetic eggs have  not been  devel-
oped or tested.

Record Keeping

     Verification of data from the SBRP soil
survey was  difficult because  the formats of
the sample  receipt  and raw  data  log  books
varied  considerably between  Laboratories A
and  B. Formats for log books and for record
keeping should be specified in the protocols
and should be reiterated during the pre-sample
audit visit. The assignment of internal labora-
tory  numbers to  the  samples  should  be
discouraged.

     Standardized forms have been developed
to record raw data from the preparation labor-
atories.  The sample  receipt  form (Figure 3)
would  include column  headings for field sam-
ple  code, dates of  sample   collection  and
sample receipt, sample condition, number of
replicate clods collected, and designation of
field duplicates and paired pedons (Coffey et
al., 1987).  The  bulk  density  raw data form
(Figure 4) would include computerized column
headings  for  field  and  laboratory weights,
water  displacement,  rock fragments,  and
special features of  the  replicate clods.  The
bulk sample raw data form (Figure 5)  would
summarize data  from  the moisture, rock frag-
ment, and inorganic carbon (or pH) determina-
tions.  Each bulk sample form would contain
data for one sample.   The completed  forms
could be sorted alphabetically  by state, numer-
ically by pedon number, and could be  used as
an index for the Form  101 data.

     Laboratory personnel could enter the raw
data into a data base  file via a compiled data
base software program, which could be acces-
sed  through a  personal  computer  without
actually using the data base software.  (Note:
A program similar to  this was generated by
ORNL and used by the  University of Tennessee
laboratory.)  Ideally, each data entry screen
would  display the  same format  as the  raw
data forms.  The  final data could be calculated
and  printed  on  the Form 101 automatically.
Entry or procedural  errors could be identified
before  a batch is sent to an analytical labora-
tory.  Data verification could  be  completed
shortly after the final batch of soil samples is
analyzed at the preparation  laboratory.  The
software  should  be  delivered  and  demon-
strated  during the  pre-sample  audit  or the
training workshop.

Design Components

     It was suggested that  a more extensive
training workshop be conducted.   The work-
shop should be held when all laboratory per-
sonnel  are  able  to  attend  and  before  soil
sampling  has  begun.  Laboratory personnel
could be instructed on the preparation proce-
dures, record keeping, and packaging samples
for  shipment.   Also, the QA auditor could
demonstrate the use  of the  data entry  com-
puter program  and could help in setting up the
sample drying  area.

     The documentation and dissemination of
the information discussed during conference
calls would  be improved if the following sug-
gestions were  implemented:

     •  The QA laboratory auditor should be
        the moderator for all conference calls.
        A staff assistant should  act in the
        place  of  the QA auditor only when
        necessary.

     •  All participants in each conference call
        should be identified.

     •  Each  conference  should  be  tape
        recorded  in  order  that  the  major
        points of the discussion can be clar-
        ified if necessary.

     •  All  pertinent  information should be
        documented by the moderator in a log
        book  set  up  specifically for this
        purpose.

     •  Log book notes  should be compiled
        monthly and should be typed and sent
        to all participants.

     After preparation laboratory operations
are underway, the conference calls  may be
reduced to bi-weekly or monthly intervals. The
conference calls should not exclude calls of an
urgent nature,  because open communication
and swift resolution of difficulties is in the
best interest of all soil survey participants.
                                           19

-------

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*"*•"



























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10



























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Cellrclid



























0|t<




























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• /




























•r


























Cor^ltlon
VtifOry (k/D)
Sloid/Unilord IS/U)
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IN)
All Heights In ±
SMI CODC




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«tf





raws
ncio op




nciB wi





Ufl_OP





I>B_HT





UULK ULIIS
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-




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                 Figure 4.  Bulk density raw data form.

-------
 SAMPLE ID:




   SITE ID:




    SET ID:




  BATCH ID:
 BULK SAMPLE RAW DATA




	    DATE SAMPLED:




	             DATE REC'D:




	          PROCESS START:




           PROCESS COMPLETE:
      SOIL TYPE:  M /  0



       Initials:
               INORGANIC CARBON:  YES /  NO




                       Initials:
SAMPLE DRYING:
Date Weight Initials
/ . g
/ • g
/ . g
/ . g
/ . g



TOTAL AIR DRY WT:
Date: / /
g
Initials:

ROCK FRAGMENT WT:
Date: / /
2 to 4.75 mm: . g
4.75 to 20 mm: . g
Initials:
 ENTERED IN COMPUTER:   Date:
                        Initials:
 COMMENTS:
Figure 5. Bulk cample raw data form.
                                 22

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     Each  set of systems audits  should be
performed  by the  same QA auditor, thereby
ensuring uniformity in the evaluation of prepa-
ration laboratory activities. The second round
of audits should be conducted after sample
processing is underway.  Audit reports should
be submitted to the QA manager within two
weeks  after returning  from an  audit, and
telephone contact should be made  within two
days  if  serious discrepancies have been
identified.
                                            23

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                                     References
Bartz,  J.  K.,  S. K.  Drous6, K.  A. Cappo,
     M. L  Papp,  G. A.  Raab, L J.  Blume,
     M.  A.  Stapanian,  F.  C. Garner, and
     D. S.  Coffey.    1987.   Direct/Delayed
     Response Project: Quality Assurance Plan
     for Soil  Sampling,  Preparation,  and
     Analysis. U. S. Environmental Protection
     Agency, Las Vegas, Nevada.

Blume,  L.  J.,   M.   L. Papp,  K.  A. Cappo,
     J. K. Bartz, D. S. Coffey, and K. Thornton.
     1987.   Soil Sampling Manual for the
     Direct/Delayed Response Project Soil
     Survey.   Appendix  A.  In   Coffey, D.
     S., J. J. Lee,  J. K.  Bartz,  R. D. Van
     Remortel, M. L Papp, and G. R. Holdren.
     1987.    Field  Operations and Quality
     Assurance Report for Soil Sampling and
     Preparation in  the Southern Blue Ridge
     Province of the United States,  Volume 1:
     Sampling. U. S. Environmental Protection
     Agency, Las Vegas, Nevada.
Cappo,  K. A.,   L  J.  Blume,  G.  A.  Raab,
     J.  K. Bartz,  and  J. L. Engels.   1987.
     Analytical  Methods  Manual  for the
     Direct/Delayed Response  Project  Soil
     Survey.     EPA  600/8-87/020.    U.  S.
     Environmental  Protection  Agency,  Las
     Vegas, Nevada.

Coffey, D. S., J.  J. Lee, J. K. Bartz, R. D. Van
     Remortel, M. L Papp, and G. R. Holdren.
     1987.   Field Operations  and Quality
     Assurance Report for Soil Sampling and
     Preparation in the Southern Blue Ridge
     Province of the United States, Volume I:
     Sampling. U. S. Environmental Protection
     Agency, Las Vegas, Nevada.

Steel, R.  G.  D., and  J. H. Torrie.    1960.
     Principles and Procedures of Statistics.
     McGraw-Hill Book Company,  New York.
     481 pp.

USDA-SCS.  1983.  National Soils Handbook,
     Parts 600-606. U. S. Government Printing
     Office, Washington, D.C.
                                           24

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                                   Appendix A
                  Preparation Laboratory Manual for the
              Direct/Delayed Response Project Soil Survey

                                         by

                         J. K. Bartz, D. S. Coffey, and L J. Blume


     The following protocols were used by preparation laboratory personnel during the Southern
Blue Ridge Province Soil Survey.   This appendix was  Part III of the  draft "Soil Sampling and
Preparation Laboratory Manual for the Direct/Delayed Response Project Soil Survey. The draft did
not undergo a full external review  and was not formally released by EPA.  It is presented here
without editorial correction.

     The protocols are preceded by a table of contents from the draft manual. Parts I and II of
the manual are presented as Appendix A in Coffey et al. (1987), referenced as follows:

Coffey, D. S., J. J. Lee, J. K.  Bartz, R.  D. Van Remortel, M. L Papp, and G. R. Holdren.  1987.  Field
     Operations and Quality Assurance Report for Soil Sampling and Preparation in the
     Southern Blue Ridge Province of the United States, Volume I: Sampling. U. S. Environmental
     Protection Agency, Las Vegas, Nevada.
                                         25

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                                                                            Section T of C
                                                                            Revision 4
                                                                            Date:  5/86
                                                                            Page 1 of 4
                                 Table of Contents



Section                                                                    Page   Revision

                                     Part I. Overview

1.0   Introduction	   1 of 2      4

                                 Part II. Field Operations

2.0   Field Personnel and Equipment	   1 of 5      4

     2.1  Personnel  	   1 of 5      4

          2.1.1   Field Crews	   1 of 5      4
          2.1.2   USD A Soil Conservation Service,
                 Soils Staff	   1 of 5      4
          2.1.3   Regional Coordinator/Correlator	   2 of 5      4
          2.1.4   Quality Assurance/Quality Control
                 Representative	   2 of 5      4

     2.2  Field Equipment	   2 of 5      4

          2.2.1   Site Selection Equipment	   2 of 5      4
          2.2.2  Excavation  Equipment  	   3 of 5      4
          2.2.3  Soil Description Equipment   	   3 of 5      4
          2.2.4  Photographic Equipment  	   4 of 5      4
          2.2.5  Clod Sampling Equipment  	   4 of 5      4
          2.2.6  Sampling Equipment 	   4 of 5      4
          2.2.7  Transportation Equipment  	   5 of 5      4

     2.3  Use of Field Equipment 	   5 of 5      4

3.0   Selection of Pedon to be Sampled  	   1 of 4      4

     3.1  Identifying a Suitable Pedon for Sampling	   1 of 4      4
     3.2  Procedure for Locating a Suitable  Pedon	   1 of 4      4
     3.3  Locating a Suitable Pedon of a Map Unit
          Inclusion	   3 of 4      4
     3.4  Paired Pedons	   4 of 4      4

4.0   Pedon Excavation	   1 of 3      4

     4.1  Standard Excavation  	   1 of 3      4

          4.1.1   Pit Size	   1 of 3      4
          4.1.2   Steps in the Pit	   2 of 3      4

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                                                                             Section  T of C
                                                                             Revision 4
                                                                             Date:  5/86
                                                                             Page 2 of 4
                            Table of Contents (Continued)


Section                                                                    Page   Revision

     4.2   Excavation of Soils with Water Tables  	  2 of  3       4
     4.3   Excavation of Organic Soils	  3 of  3       4
     4.4   Soils Difficult to Excavate	  3 of  3       4

5.0  Site and Profile Description	  1 of  3       4

     5.1   Profile Preperation	  1 of  3       4
     5.2   Photographs of Profile and Site 	  1 of  3       4
     5.3   Thick Horizons	  2 of  3       4
     5.4   Field Descriptions  	  2 of  3       4
     5.5   Documents  	  3 of  3       4

6.0  Field Sampling Procedures	  1 of  6       4

     6.1   Sampling the Pedon	  1 of  6       4

           6.1.1   Field Sampling Protocol	  1 of  6       4
           6.1.2  Important Points Concerning Soil
                 Sampling	  1 of  6       4

     6.2   Sample Size  	  1 of  6       4
     6.3   Sampling Procedure	  2 of  6       4

           6.3.1   Stratified Horizons	  2 of  6       4
           6.3.2  Field Duplicates	  2 of  6       4

     6.4   Sampling Clods for Bulk-Density Determination	  2 of  6       4

           6.4.1   Procedure	  3 of  6       4
           6.4.2  Transport of Clods  	  3 of  6       4

     6.5   Filling Sample Bag	  3 of  6       4
     6.6   NADSS Label A	  4 of  6       4
     6.7   Delivery	  5 of  6       4

                              Part III. Preparation Laboratory

7.0  Preparation Laboratory  Personnel and Equipment  	  1 of  3       4

     7.1   Personnel  	  1 of  3       4
     7.2   Equipment	  1 of  3       4

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                                                                            Section  T of C
                                                                            Revision 4
                                                                            Date:  5/86
                                                                            Page 3 of 4
                            Table  of Contents (Continued)

Section                                                                    P^tge   Revision
8.0  Receipt and Storage of Samples	   1 of  1       4
     8.1    Bulk Soil Samples  	   1 of  1       4
     8.2   Clods for Bulk Density	   1 of  1       4
9.0  Sample Processing	   1 of  6       4
     9.1    Air Drying  	   1 of  6       4
           9.1.1   General Considerations	   1 of  6       4
           9.1.2   Procedure	   1 of  6       4
     9.2   Crushing and Sieving	   2 of  6       4
           9.2.1   General Considerations	   2 of  6       4
           9.2.2  Procedure	   3 of  6       4
           9.2.3  Calculation of Percent Rock Fragments  	   4 of  6       4
     9.3   Homogenization and Subsampling  	   4 of  6       4
           9.3.1   General Considerations	   4 of  6       4
           9.3.2  Procedure for Analytical Samples	   5 of  6       4
           9.3.3  Procedure for Mineralogical Samples  	   5 of  6       4
     9.4   Documentation 	   6 of  6       4
10.0 Formation  and Shipping of Batches  	   1 of  2       4
     10.1   Analytical Samples	   1 of  2       4
           10.1.1  Procedure	   1 of  2       4
     10.2  Mineralogical Samples	   2 of  2       4
11.0 Analytical Procedures	   1 of  5       4
     11.1   Rock Fragments   	   1 of  5       4
           11.1.1  Procedure	   1 of  5       4
           11.1.2 Calculations  	   1 of  5       4

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                                                                            Section  T of C
                                                                            Revision 4
                                                                            Date:  5/86
                                                                            Page 4 of 4
                            Table of Contents (Continued)


Section                                                                    Pagg

      11.2  Moisture  	   1 of 5      4

           11.2.1  Procedure	   1 of 5      4
           11.2.2  Calculations  	   2 of 5      4

      11.3  Inorganic Carbon	   2 of 5      4

           11.3.1  Procedure	   2 of 5      4
           11.3.2  Internal Quality Control	   3 of 5      4

      11.4  Bulk Density  	   3 of 5      4

           11.4.1  Procedure	   3 of 5      4
           11.4.2  Assumptions	   4 of 5      4
           11.4.3  Calculations  	   5 of 5      4

12.0   References	   1 of •)      4


Appendices

      A    Strategy of Site Selection and Sampling
           Information for the Northeastern United States	   1  of 10      4

      B    Strategy of Site Selection and Sampling
           Information for the Southeastern United States  	   1  of 2      4

      C    Field Data Form and Legends  	   1 of 59      4

      D    Preparation  Laboratory Forms  	   1  of 3      4

      E    List of Northeast Soils by Sampling Class  	   1  of 6      4

      F    List of Southern Blue Ridge Soils by
           Sampling Class	   1 of 12      4

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                                                                     Acknowledgements
                                                                     Revision 4
                                                                     Date:  5/86
                                                                     Page 1 of 1
                               Acknowledgments
     Contributions provided by the following individuals were greatly appreciated:  S. Bodine, D.
Lammers, M. Johnson, J.  Lee, B.  Jordan, M.  Mausbach, R.  Nettleton, W. Lynn, F. Kaisacki, B.
Waltman, W. Hanna, B. Rourke, G. Raab, and J. Warner.

     The following people were instrumental in the timely completion of this manual:  Computer
Sciences Corporation word processing staff at the Environmental Monitoring Systems Laboratory-
Las Vegas, C. Roberts at the Environmental Research Laboratory-Corvallis, J. Engels, M. Faber, and
G. Villa at Lockheed Engineering and Management Services Company, Inc., and Mary Lou Putnam
of Donald Clark Associates.

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                                                                        Section 7.0
                                                                        Revision 4
                                                                        Date:  5/86
                                                                        Page 1 of 3
                    Part III.   Preparation Laboratory




7.0  Preparation Laboratory Personnel and Equipment


7.1   Personnel

Personnel at the preparation laboratory will be responsible for distributing equipment and supplies
provided by EMSL-LV to the field crews for maintaining an adequate inventory of supplies for the
duration of the survey, and for returning all provided equipment and unused supplies to EMSL-LV
at the close of the survey.

The preparation laboratory is also responsible for obtaining the acetone necessary for mixing the
saran:acetone that is used by both the field crews and the preparation laboratory for the collection
of clods and for the analysis of samples for bulk density.

The preparation laboratory is responsible for keeping complete documentation for the tracking of
samples during storage and through the preparation procedures. The laboratory may be required
to provide this documentation to the EPA project  officer or designee during the course  of the
project.  Required documentation must be submitted to the EPA upon conclusion of the survey.

The preparation laboratory is responsible for receipt of bulk soil samples and clods from the field
crews and  is also  responsible for following the specified  protocol for all aspects of storage.
processing, subsampling, batching, and shipping of samples.  The laboratory is responsible for
performing the specified analytical procedures, i.e., bulk density, percent air-dry moisture, percent
rock fragments, and the qualitative test for inorganic carbon and for keeping accurate and  legible
data books. The data books will be  bound, kept in black ink, dated and signed by the analysts,
with all erroneous entries initialed and crossed out so that they remain legible.  The laboratory is
responsible for reassignment of field samples to analytical batches and for keeping supporting
documentation which includes  the NADSS label A logbook and NADSS forms 101 and 102.

The manager of the preparation laboratory will be a person experienced in processing soil samples
and organized  in the tracking of samples through the laboratory.

7.2  Equipment

The preparation laboratory will be equipped to perform the specified protocol. A partial listing of
equipment follows;  items marked  with an asterisk will be provided by EMSL-LV:

     •  Logbooks*

     •  Plastic and cloth sample bags*

     •  Twist  ties for sample  bags*

     •  Brown or white paper

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                                                                      Section 7.0
                                                                      Revision 4
                                                                      Date:  5/86
                                                                      Page 2 of 3
•  Drying trays
•  Dehumidifier
•  Wooden rolling pin
•  Sieves, 2-mm mesh and 4.75-mm mesh
•  Jones-type, riffle splitter with 1.25-cm openings
•  Scale or two-pan balance
•  NADSS labels A and B*
•  NADSS forms 101 and 102*
•  Pens, permanent ink*
•  Bottles, 500-ml plastic*
•  Shipping boxes*
•  Packing material
•  Strapping tape*
•  Air courier account number*
•  Porcelain spot plate
•  Squeeze bottle or eyedropper for deionized water
•  Microscope or stereoscope (10x or higher)
•  4 N HCI
   Quality control detection limit sample, i.e., soil spiked with 1  percent (wt/wt) CaCO, or
•  Quality control calibration sample (QCCS) test soil spiked with5% (wt/wt) CaCO3
•  QCCS test soil spiked with 5% (wt/wt) CaMgCO3
•  Top-loading balance
•  Analytical balance
•  Drying oven
•  Muffle furnace

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                                                                     Section 7.0
                                                                     Revision 4
                                                                     Date:  5/86
                                                                     Page 3 of 3
•  Laboratory equipped with house air, fume hoods, safety equipment

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                                                                         Section 8.0
                                                                         Revision 4
                                                                         Date: 5/86
                                                                         Page 1 of 1
8.0  Receipt and Storage of Samples
8.1   Bulk Soil Samples

Samples are received at the preparation laboratory as soon as possible after sampling. Keep a
logbook to record the following information: date received; time received; who delivered samples;
who received samples; condition of samples, noting only problems specifically by sample code, e.g.,
if the samples were not held at 4°C prior to delivery  or  if  a sample  container broke and
contamination  is possible; set  ID numbers; and total number of samples.   The field crew is
responsible for registering samples upon delivery unless laboratory personnel decide to accept this
responsibility.

Unless the samples are taken immediately to the processing area and are  spread out to air-dry,
place  the samples in cold storage upon receipt. Return samples to cold storage after drying and
whenever they are not undergoing processing as described  in Section 9.0.   Maintain the cold
storage locker  at 4*C and monitor the temperature on a daily basis. Record any deviations  in the
temperature in  a logbook and identify those samples affected by the change in temperature by set
ID and, if necessary for clarity, by sample code.

Keep samples organized so that a particular sample may be located easily.  Shelving of some kind
is necessary to maximize the use of available space and to facilitate organization of the samples.

8.2  Clods for Bulk  Density

Clods are received at the preparation  laboratory along with the bulk samples. A separate logbook
is kept to record the receipt of clods.

Remove the label from each clod  and staple  it  in the logbook.  Immediately relabel the clod with
the sample code and assign a replicate number to provide a unique identity for each clod.  Also,
record the date of receipt, the condition of  each clod, the number of saran  coatings, and the
assigned replicate number.

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                                                                           Section 9.0
                                                                           Revision 4
                                                                           Date:  5/86
                                                                           Page 1 of 6
9.0  Sample Processing


Specific areas will be designated for sample processing.  During all steps of processing, sample
integrity is of the greatest importance. This is protected by maintaining the unique identity of each
sample by labeling with the sample code, by documenting each sample through all processing, and
by avoiding physical and chemical contamination during each processing step.

9.1   Air Drying

9.1.1  General Considerations

The area designated for air-drying samples must have adequate bench space to allow several sets
of samples,  i.e., approximately 60 samples, to be drying simultaneously. Also, it is important that
there be a method to reduce relative humidity in the room, e.g., by removing moist air via a fume
hood  or by  reducing humidity with  a dehumidifier.  If  available, a temperature- and humidity-
controlled greenhouse environment is ideal for drying samples.  The area or room  must be secure
and have limited access.

In evaluating an area for air-drying samples, sources of potential contamination, including growing
plants, other sample types, dust, and chemicals such as fertilizers or pesticides, will be identified
and eliminated. Handling samples without  wearing gloves is a source of contamination as is the
talc which is used on some plastic or rubber gloves.

Soils high in clay may harden irreversibly if allowed to dry completely prior to crushing; therefore,
crush such soils  before they reach a constant moisture  content.  Then continue air-drying after
the crushing procedure (described in Section 9.2)  and determine the  moisture content after the
air-drying is  completed.  It may be desirable to  hold partially dry soils that are high in clay in cold
storage until crushing may be scheduled.

9.1.2  Procedure

9.1.2.1  Spread the sample on a new sheet of white or brown paper large enough to allow paper
       to be exposed on all sides of the sample.  The paper may be placed on a tray or directly
       upon the  bench top.

9.1.2.2 Occasionally stir the soil with a clean stainless-steel spoon to facilitate drying. Water may
       condense on the tray or bench top, creating an undesirable situation that would maximize
       conditions for microbial growth.  An arrangement allowing for air circulation  below the
       sample is preferred.   For example, frames with screen bottoms may be used in place of
       trays,  or the bench top may be made  of steel netting.  As an alternative, place several
       layers of paper below the paper containing the sample and replace those layers when they
       become damp.  Any observations of fungal or algal growth should be noted by sample code
       in the  sample tracking log book.

9.1.2.3 Allow the sample to  air-dry until it achieves a constant moisture content, i.e., until it is in
       equilibrium with the relative humidity.  This step may require a period of two days or more
       than three weeks, depending upon the character of sample.

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                                                                            Section 9.0
                                                                            Revision 4
                                                                            Date:  5/86
                                                                            Page 2 of 6


        Test each sample for moisture content as described  in Section 11.2.  Constant air-dry
        moisture content is achieved when the moisture content is not reduced by more than an
        absolute 2.5 percent in two consecutive days. After the sample  passes this test, it may
        undergo further processing immediately or be placed in a  new plastic bag, sealed, and
        placed in cold storage until further processing is possible.

9.1.2.4  On rainy days or during periods of high  relative humidity, a sample may adsorb moisture;
        therefore, determinations of moisture may show  an increase in moisture content.  Do not
        rebag a  sample  that has increased in moisture  content because of such  weather
        conditions.  Allow additional, less humid days for it to dry. If necessary, replace the damp
        paper below the sample.

9.2  Crushing and Sieving


9.2.1 General Considerations

A fume hood with  inspected and  properly functioning fans, vents, and filters,  is the preferred
location for crushing and sieving samples. It is a relatively small area that can be  covered with
protective layers of paper and that can be cleaned easily. Also, the exhaust removes small soil
particles that would otherwise contaminate the work area and that would be  inhaled by the
technician.

An area near a source of compressed  air is  desirable because the air can be used to clean the
surfaces of the equipment, i.e., wooden rolling pin, 4.75-mm mesh  sieve, and 2-mm mesh sieve,
after the processing of each sample. However, water and oil tend to accumulate in the conduit and
to spray out occasionally from in-house, compressed-air  lines.  This would represent a source of
contamination. Therefore, the air must be passed through a trap to collect the offending water and
oil

Such a  trap can be assembled by using an Erlenmeyer flask, a small piece of cotton cloth or
several  Kimwipes, a one-holed rubber stopper sized to fit the flask, a piece of glass or plastic
tubing long enough to extend through the rubber stopper and well past the side arm of the flask,
and  two lengths of  vinyl tubing.  Place  the cloth or Kimwipes into the flask.  Insert the glass or
plastic tubing through the rubber stopper and stopper the flask.  Connect the side arm of the flask
to the air nozzle with a short length of  vinyl tubing.  The second length of vinyl tubing should be
long enough to reach from the position of the flask to the work area. Attach it to the  exposed end
of the glass or plastic tubing which is  in the rubber stopper.  If water or oil is observed in this
length of vinyl tubing when using air to clean the equipment, the cloth  or Kimwipes should be
replaced, and the tubing should be cleaned out before continuing.  Occasionally, the air pressure
may be too high for this apparatus, and this will cause the rubber stopper to  blow out. This
problem can be corrected by adjusting the delivery of air  from the nozzle.

In addition to cleaning the equipment with  compressed air, the  surfaces may  be wiped with
Kimwipes if soil is adhering to the wooden rolling pin or to the frame of the sieve.  Used Kimwipes
should be discarded after cleanup for each sample processed to avoid contamination. Sieves which
have been cleaned with compressed air will be rinsed with deionized water and will be  thoroughly
air-dried or oven-dried at the end of each day.  Brass sieves should be removed from the drying
oven as soon as they are dry because brass will oxidize at temperatures as low as  60"C.

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                                                                            Section 9.0
                                                                            Revision 4
                                                                            Date:  5/86
                                                                            Page 3 of 6


Large pieces of stems and roots that are obviously not part of the soil should be removed when
encountered in the processing described in Section 9.2.2.

Caution:   Rock fragments in soils of the Southeast are likely to be relatively soft either because
           they  are  of sedimentary origin or because they have  been subjected to intensive
           weathering. Using a wooden rolling pin as  specified in the procedure below will crush
           these soft rock fragments. This will result in an underestimation of percentage rock
           fragments in the laboratory as compared to the field  estimates and also will result in
           a sample of questionable  integrity because it contains crushed rock material.  When
           rock fragements are soft and easily crushed, the procedure may be modified according
           to the alternatives specified in the appropriate subsections below.

9.2.2 Procedure

9.2.2.1  Record the weight of  the whole sample  prior to crushing and sieving. Any sample lost
        during the processing is most likely to be from the less than 2-mm fraction.

9.2.2.2  Spread a small portion of sample on an approximately 60-cm by 60-cm piece of brown or
        white paper. Another layer of paper may be placed over the  sample, if desired.  Crush the
        sample  with the rolling pin; apply only enough force to disaggregate the clods or soil
        structure, but not so much force that weathered rocks are crushed.  Go to Section 9.2.2.3.

        Alternative:   Place a portion of sample in the  2-mm sieve and gently push the soil through
                     the sieve with a rubber stopper.  Attempt to include soil adhering to the rock
                     fragments.  Continue  until  the entire sample  is processed.  Go to Section
                     9.2.2.5.

9.2.2.3  After each portion  is crushed, set the portion  aside and repeat with another aliquot until
        the entire sample is prepared. Go to Section 9.2.2.4.  Alternatively, each  portion may be
        sieved as described in Section 9.2.2.4 before continuing with another portion of sample.

9.2.2.4  Either nest the two sieves with the 2-mm mesh sieve on  the bottom or use only the 2-mm
        mesh sieve for this step. Place the sieve(s) onto an approximately 45-cm by 45-cm piece
        of brown or white  paper. Pour aliquots of soil onto the sieve (s). Move the sieve (s) from
        side to  side, gently tapping  the side of the sieve(s) to facilitate the passage  of sample
        through the mesh.  Do not press sample through the sieve (s).  If peds are retained by the
        sieve(s), remove that material from the  sieve(s) and crush as described in Section 9.2.2.3.
        Continue sieving until all material has been  processed. Save the less than 2-mm material
        in plastic sample bags and return to cold storage or immediately continue with processing
        as described in Section 9.3.

9.2.2.5  If both  the 4.75-mm and 2-mm sieves  were used  in Section 9.2.2.4, continue  at Section
        9.2.2.6.

        If only the 2-mm mesh sieve was used in Section 9.2.2.4, sieve all rock material which was
        retained by the 2-mm mesh sieve through  the 4.75-mm  mesh sieve. Catch the material
        which passes the sieve on a piece of paper.

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                                                                           Section 9.0
                                                                           Revision 4
                                                                           Date:  5/86
                                                                           Page 4 of 6


        Alternative:   A significant amount of soil may adhere to the soft rock fragments.  Wash
                     the  fragments with  deionized water while they  are on the  sieve.   Then
                     continue with  Section 9.2.2.6.

 9.2.2.6  Weigh the material retained  by the 4.75-mm sieve.  Record the weight as that of the 20-
        to 4.75-mm rock fragments.

 9.2.2.7  Weigh the material retained  by the  2-mm sieve. Record the weight as that of the 4.75- to
        2-mm rock fragments.

 9.2.2.8  Combine the rock fragments  in a plastic sample bag and label with the appropriate sample
        code.

        If the qualitative test for inorganic carbon as described in Section 11.3 is positive, crush the
        rock  fragments to pass a  2-mm  mesh sieve. Use a Jones-type riffle splitter first to
        homogenize the sample and then to obtain a 100-g subsample. Crush the entire subsample
        to pass an 80-mesh sieve.  Place it in a plastic sample bag labeled with the appropriate
        NADSS label.  If crushing of rock fragments is done prior to sample batching,  the 100-g
        subsample is labelled initially with NADSS Label A which is later replaced with NADSS Label
        B.  If sample  batching is done prior to the determination of inorganic carbon,  the 100-g
        subsample is  labeled with NADSS Label B.  Place the plastic bag in a  cloth sample bag.
        Keep this subsample with the appropriate 1-kg analytical subsample for shipment to the
        analytical laboratory as described in Section 10.0.

        Save all rock fragment samples until instructed to discard them or to ship them to another
        location.  Cold storage is not required for rock fragments.

 9.2.3  Calculation of Percent Rock  Fragments

The percentage of rock fragments in each size faction,  i.e., 20- to 4.75-mm and 4.75- to 2-mm, is
calculated as follows:

                                              ([weight of size fraction] \
                                              	 100
                                                   [total weight]     j

9.3  Homogenization and  Subsampling


9.3.1  General Considerations

A fume  hood is the preferred location for homogenization and subsampling the less than 2-mm
fraction. It should be  prepared as described in Section 9.2.1.

A Jones-type riffle splitter with 1.25-cm openings is used for both homogenization and subsampling.
The riffle splitter will be cleaned between each sample with compressed air as described in Section
9.2.1. The surfaces may be  cleaned with a brush, if necessary.

It will be cleaned with deionized water and allowed to thoroughly air-dry after each day of use.
Prior to  use, the riffle spitter should be inspected to verify that it is dry.

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                                                                           Section 9.0
                                                                           Revision 4
                                                                           Date:  5/86
                                                                           Page 5 of 6


A scale or two-pan balance must be available to weigh the 1-kg analytical sample or the 500-g
mineralogical sample.

Because (1) only a few horizons will be chosen for mineralogical analyses from all routine  samples
collected and (2) the identification of those horizons is made after all samples have been collected,
samples for mineralogical analyses will be split at some time  after those for analytical analyses
are split.

9.3.2 Procedure  for Analytical Samples

9.3.2.1  Position the  receiving pans on each side of the riffle  splitter.  Pour the less than 2-mm
        material evenly across the baffles of the riffle splitter.  Repeat six times in succession for
        the material  in each receiving pan to ensure  that the sample  is thoroughly homogenized.

9.3.2.2  Transfer the  entire sample to one receiving pan or pour it onto a new square of brown or
        white paper,

        Place the receiving pans on each side of the riffle splitter. Pour the sample evenly across
        the baffles. Place the material from one receiving pan into a plastic sample  bag.  With the
        material in the other receiving  pan, repeat the procedure  as required until a subsample of
        approximately 1 kg  is obtained.

        It is  important  that the subsample be obtained entirely by splitting with the riffle splitter.
        An alternate  method of using the riffle splitter to obtain the 1-kg subsample  follows:  After
        an easily handled amount of sample is split out, a subsample of 1 kg  may be obtained by
        splitting the material and allowing the material to remain in both pans.  Then the material
        from one pan is passed through the splitter again, so that one pan now contains 3/4 of
        the material  and the other pan contains 1/4 of  the material.  Place the smaller amount of
        material in the sample bag and continue to split in this manner until the 1-kg sample Is
        obtained.  If only a small  amount  of  material is needed to attain the 1-kg subsample,
        successive  splits of the material may be made so  that the pan  containing the lesser
        amount of material contains 1/8, 1/16, 1/32, and so on, and the pan containing  the greater
        portion of material  contains 7/8, 15/16, 31/32, and so on.

9.3.2.3  Place the 1-kg subsample in a plastic sample bag and secure with a twist tie.  Label with
        NADSS Label A or,  if an analytical batch is being assembled  as described in Section 10.0,
        NADSS Label B may be placed on the 1-kg subsample.  The sample may be double-bagged
        in plastic for security.  Place the plastic bag in a cloth bag and return  the subsample to
        cold  storage as soon as possible.

9.3.2.4  Label remaining sample material with NADSS Label A  Place the plastic bag in  a cloth bag
        and  return the  sample to cold storage for  archiving. Sets  will be packed according to
        sample code for permanent archiving.

9.3.3  Procedure for Mineralogical Samples

9.3.3.1  Rehomogenize  the less than 2-mm material as described in Section 9.3.2.1.

9.3.3.2  Split out a 500-g subsample as described in Section 9.3.2.2.

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                                                                          Section 9.0
                                                                          Revision 4
                                                                          Date:  5/86
                                                                          Page 6 of 6


9.3.3.3 Place the 500-g subsample in a 500-mL air-tight plastic bottle.  Label the bottle with the
       sample code and return the sample to cold storage until it is shipped.

9.4  Documentation

In addition to data books used for entry of raw data for determination of percent moisture and
percent rock fragments, records will be kept to document the date(s) of sample processing.  Also
the weight of the less than 2-mm material obtained after sieving, the percent rock fragments in the
20- to 4.75-mm fraction, and  the percent rock fragments in the 4.75- to 2-mm fraction will  be
entered into the NADSS Label  A logbook described in Section 10 11 4

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                                                                         Section 10.0
                                                                         Revision 4
                                                                         Date:  5/86
                                                                         Page 1 of 2
10.0  Formation and Shipping of Batches
10.1   Analytical Samples

A batch of samples for chemical and physical analysis by a contractor laboratory consists of a
maximum of 39 routine samples and field duplicates.  Depending upon the number of samples in
each set, i.e., a group of samples taken by one field crew in 1 day, a batch may include up to six
sets In addition, one sample per batch is chosen as the preparation duplicate and is split into two
subsamples according to the procedure in Section 9.4. Two audit samples supplied by the quality
assurance staff will be specified for each batch. Therefore, one batch including routine samples
field duplicates, a preparation duplicate,  and two audit samples will contain  a maximum of 42
samples.

 10.1.1  Procedure

10111  After deciding which sets  will be included in the analytical batch, randomly choose one
        sample to be the preparation duplicate.   The  horizon-type chosen as the preparation
        duplicate should vary from batch to batch so that all horizon-types are chosen at least
        once   Rehomogenize the archived sample  material  for  the chosen sample  by seven
        successive passes through a Jones-type riffle  splitter. Then split out a subsample as
        described in Section 9.4.

10 11 2  Randomize the  samples in the batch.  Assign sample numbers from 1  through 42, as
        needed.  Record the site ID, sample code, and  set ID on NADSS Form 101.

        The sample code for a preparation duplicate will begin with three alpha characters, PLD,
        and end with the same  last 10 digits as the routine sample from which it was split. For
        example, the preparation  duplicate split from routine sample R11NH01300405 would be
        designated as PLDNH01300405.

        The sample code for an audit sample would begin with the first three characters of the
        horizon designation and would be followed by two zeros, the  three-digit audit  number
        specified by the quality assurance staff, a hyphen, and four zeros.  For example, the audit
        sample prepared from soil sampled from an argillic, maximum B  horizon would begin with
        the three characters, B+2.  If the horizon designation includes less than three characters,
        the spaces are filled in  with zeros.

        Set NADSS Form  101 aside until the remaining data for weight percent rock fragments,
        weight percent air-dry moisture,  soil type, presence of inorganic carbon, and bulk density
        may be entered from the appropriate data books.  For sample tracking purposes, it  is
        important that this form be sent as soon as possible. After it is completed, Form 101 will
        be submitted to the following address:

                Lockheed Engineering & Sciences Company
                1050 East Flamingo,  Suite 200
                Las Vegas, Nevada  89119

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                                                                           Section 10.0
                                                                           Revision 4
                                                                           Date: 5/86
                                                                           Page 2 of 2
 10.1.1.3  Fill out NADSS Label B for each sample.  This label includes only the batch number and
         the sample number assigned above.

 10.1.1.4  Remove NADSS Label A from each sample and replace it with NADSS Label B.  Staple
         NADSS Label A in a logbook and initial the label so that the writing overlaps both the label
         and the page.  Indicate in the logbook the newly assigned batch  and sample numbers.
 1°'1'1'5 fJI!,2tN^StF°T  I?2'  Remove the white (ori9inal> c°Py and send  jt via overnight
        courier to the Sample  Management Office at the following address:

                Sample Management Office (Viar)
                300 North Lee Street
                Alexandria, Virginia 22314

        The remaining copies are left intact and are included inside the packed box(es).

 10.1.1.6 Each sample should now be labeled with only the newly assigned batch  ID and sample
        number.  Place each plastic bag of sample in a  cloth bag. Secure the cloth bag so that
        any sample that might leak from the plastic bag  will be contained by the cloth baa  Pack
        the samples securely,  by using additional packing materials as needed.

 10.1.1.7 Store the packed boxes under refrigeration at 4  eC until they are to be shipped.

 10.1.1.8 Send the box(es) containing the designated analytical batch to the contractor laboratory
        specified by the quality assurance staff. An overnight air courier service will be specified
        for all shipments, and an account number will be supplied for billing shipments to a third
        party.

 10.2  Mineralogical Samples
nfJJStr for .minerflo9'cal analysis will be combined into batches  of  20 routine samples, 3
£252!  • duphcate!' a"d ? audit samP|es at EMSL-LV. The subsamples will be shipped via
fo^SlT ST-10 tnef°lowin9 address  where they will  be combined  into batches and
forwarded to the designated mineralogical laboratory:
               Lockheed Engineering & Sciences Company
               1050 East Flamingo Road, Suite 200
               Las Vegas, Nevada 89119

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                                                                          Section 11.0
                                                                          Revision 4
                                                                          Date: 5/86
                                                                          Page 1 of 5
11.0  Analytical Procedures
11.1   Rock Fragments

The term "rock fragments" is defined in Soil Taxonomy as "particles 2 mm in diameter or larger
and includes all sizes that have horizontal dimensions less than the size of a pedon." Only the 20-
to 4 75-mm fraction and the 4.75- to 2-mm fraction are determined in the preparation laboratory.
The percentage of rock fragments is determined on the basis of the weight of sample brought into
the laboratory for processing.

 //. /. /  Procedure

11111  Record the weight of the whole sample  prior to crushing and sieving. Any sample lost
        during the processing described in Section 9.2 is most likely to be from the less than 2-
        mm fraction.

11.1.1.2  Weigh the material retained by the 4.75-mm  sieve.  Record the  weight as that of the 20-
        to 4.75-mm rock fragments.

11.1.1.3  Weigh the material retained by the 2-mm  sieve.  Record the weight as that of the 4.75- to
        2-mm rock fragments.

 11.1.2  Calculations

The percentage of rock fragments in each size faction, i.e., 20- to 4.75-mm and 4.75- to 2-mm,  is
calculated as follows:

                                    ([weight of  size fraction] \
                                    	  100
                                         [total weight]    J

 11.2   Moisture

 Moisture content is determined on a 15- to  20-g grab sample  taken after the air-dry sample
described in Section 9.1.2.2 has been thoroughly mixed. Two convection-type drying ovens are
preferred for this procedure if both mineral and organic soils are tested  because mineral soils are
dried at ± 5 *C and organic soils are dried at 60 *C ± 5 *C.  Each oven must equilibrate at the
appropriate temperature for 24 hours prior to  use. If only one drying oven is available, allow 24
hours for the temperature to equilibrate after an adjustment is made from one temperature to the
other.  The range of the thermometers used to measure oven temperature will be 0 to 200  C.

 11.2.1 Procedure

 11.2.1.1  Thoroughly mix the air-dried soil.  Transfer a 15- to 20-g sample to an aluminum weighing
        dish which is not to exceed 2 g in weight. Handle the weighing dish with forceps or finger
        cots.

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                                                                             Section 11.0
                                                                             Revision 4
                                                                             Date:  5/86
                                                                             Page 2 of 5


 11.2.1.2  Record the initial weight of sample and weighing dish to the nearest 0.01 g. Because the
         aluminum weighing dishes are manufactured to be a nearly-consistent weight, the average
         weight of 10 aluminum weighing dishes may be used as the tare weight.

 11.2.1.3  Dry the sample overnight or for 16 hours in a drying oven which  is equilibrated  at the
         appropriate temperature.

 11.2.1.4  Remove the  sample from the oven  and allow it to cool for  at least 30 minutes in a
         desiccator.  Then record the oven-dried weight of the sample and weighing dish.

 11.2.1.5  On the following day, transfer a second 15- to 20-g sample from the central portion of the
         air-dried material to an aluminum weighing dish.  Repeat steps 11.2.1.2 through 11.2.1.4.

 11.2.1.6  If the calculated moisture contents differ by more than an absolute  2.5 percent, allow the
         sample to continue air-drying and retest it  at a  later time. However, if the calculated
         moisture contents do not differ by more than 2.5 percent in two consecutive days, the air-
         dry sample may undergo processing  as described in Section 9.0.

 11.2.2  Calculations

                            I [air-dried weight - oven-dried weightn
         Percent moisture =		  100
                            \        [oven-dried weight]           /

 11.3  Inorganic Carbon

The less than 2-mm  fraction is tested qualitatively for the presence of carbonate minerals, i.e.,
inorganic carbon. If carbonate minerals are present in the soil at levels of approximately 1 percent
or higher, effervescence is observed after the  addition of 4 N HCI.

When a sample is found to contain inorganic  carbon  by using this test, both the less than  2-mm
material and the 20- to 2-mm rock fragments are submitted to the analytical laboratory for analysis
Refer to Section 9.2.2.8.                                                                   '

 11.3.1  Procedure

11.3.1.1  Place 1 g of less than 2-mm soil material in a well of a porcelain spot plate.  Thoroughly
        moisten the soil with a few drops of deionized water; stir with a clean glass rod to remove
        entrapped air.

11.3.1.2  Add  three drops of  4 N HCI and immediately observe the treated sample under a light
        microscope or stereoscope. Be careful not to get acid on  lens or  lens sealant.  If this
        occurs, wash  off acid  and clean and  dry  lenses.  Record presence  or absence of
        effervescence for each sample according to sample code.

11.3.1.3  Repeat the treatment and the observation with a second 1-g sample.

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                                                                           Section 11.0
                                                                           Revision 4
                                                                           Date:  5/86
                                                                           Page 3 of 5



11.3.2  Internal Quality Control

Both a quality control (QC) detection limit sample and a quality control calibration sample (QCCS)
are required for this procedure.  The purpose of the QC samples is to ensure that the technician
is able to distinguish effervescence.

The QC detection limit sample is prepared by spiking an aliquot of non-carbonate soil with 1 percent
(wt/wt) CaCO3 or CaMgfCO^.  The QC detection limit sample is analyzed prior to sample analysis
and after each 10 or fewer samples.

The QCCS  is prepared  by spiking an aliquot of non-carbonate soil with 5 percent (wt/wt) CaCO3
or CaMg(CC>3)2. The QCCS is analyzed prior to sample analysis and after each twenty  or fewer
samples.

11.4  Bulk Density

Density is defined as mass per unit volume expressed in units of g/cm3.  The bulk density of a soil
is defined as the  mass of dry soil per unit volume including the pore space.  The bulk volume is
determined prior to drying the soil to constant weight, at 105 *C for mineral soils and at 60  C for
organic soils.

Bulk density of mineral soils generally ranges between 1.0 and 2.0 g/cm3. Soils that are porous
will have low bulk density values, and  soils that are compacted will have high bulk density values.
With increasing organic matter content, soils generally exhibit a decrease in bulk density because
(1) organic matter is less dense than mineral particles of the  same size and  (2) organic matter
promotes granular soil structure with  a resulting increase in porosity.

 11.4.1  Procedure

11.4.1.1  Weigh the  clod as received from the field crew.  Record the initial weight as m,. Clods
        weighing more than 100 g are weighed to the nearest 0.1 g; clods weighing less than 100
        g  are weighed to the nearest 0.01 g.

11.4.1.2  Briefly dip the clod into a 1:7 (wt/wt) saran-acetone mixture. Then suspend the clod from
        a  line and allow the clod to dry.

11.4.1.3  Reweigh the clod and record this weight as m2.

11.4.1.4  Repeat steps  11.4.1.2 and  11.4.1.3 as necessary until a coating of saran that is impervious
        to water is obtained.  Record each additional weight as m3, m4	m,.

11.4.1.5  Degas approximately 800 mL of deionized water in a  1-L beaker by boiling until no rising
        gas bubbles are observed. Cover the beaker with a watch glass and allow the water to
        cool to room temperature.

11.4.1.6  Place the beaker of degassed water on a balance and record the tare weight. Also, record
        the temperature of the water  so that the density of the water may be obtained from Table
        11.1.

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                                                                              Section 11.0
                                                                              Revision 4
                                                                              Date:  5/86
                                                                              Page 4 of 5
 Table 11.1.  Density* of Water
 4C
0
10
20
30
40
50
60
70
80
90
0.9999
0.9997
0.9982
0.9957
0.9922
0.9881
0.9832
0.9778
0.9718
0.9653
0.9999
0.9996
0.9980
0.9954
0.9919
0.9876
0.9827
0.9772
0.9712
0.9647
1.0000
0.9995
0.9978
0.9951
0.9915
0.9872
0.9822
0.9767
0.9706
0.9640
1.0000
0.9994
0.9976
0.9947
0.9911
0.9867
0.9817
0.9761
0.9699
0.9633
1.0000
0.9993
0.9973
0.9944
0.9907
0.9862
0.9811
0.9755
0.9693
0.9626
1.0000
0.9991
0.9971
0.9941
0.9902
0.9857
0.9806
0.9749
0.9686
0.9619
1.0000
0.9990
0.9968
0.9937
0.9898
0.9852
0.9800
0.9743
0.9580
0.9612
0.9999
0.9988
0.9965
0.9934
0.9894
0.9848
0.9795
0.9737
0.9673
0.9605
0.9999
0.9986
0.9963
0.9930
0.9890
0.9842
0.9789
0.9731
0.9667
0.9598
0.9999
0.9984
0.9960
0.9926
0.9885
0.9838
0.9784
0.9724
0.9660
0.9591
  Also the specific gravity or unit weight of water in grams per milliliter.


 11.4.1.7  Suspend the clod over the beaker.  Lower the clod gently into the water until it is totally
         submerged. Record the weight displayed on the balance as weight of water supporting
         clod.


 11.4.1.8  Suspend the clod in a drying oven at the appropriate temperature for 48 hours: 105 *C for
         mineral soils and 60 *C for organic soils. Moisture from within the clod will diffuse through
         the saran coating.


 11.4.1.9  Remove the clod from the oven  and allow it to cool in a desiccator.  Weigh the clod to
         obtain the oven-dried weight.


 11.4.1.10  For mineral soils, place the clod in a container that will withstand 400  *C. Place the clod
         and container  in a muffle furnace  that is equilibrated at 400  *C and allow  the saran to
         vaporize from  the clod over the  next 2 hours. The muffle furnace must be placed in a
         fume hood:  saran is a carcinogen.


         Remove the container and contents  from the  muffle  furnace  and allow  to  cool  in a
         desiccator.  Weigh only the  contents of  the container.  Record the weight of the soil
         particles.


11.4.1.11  Pass the sample through a 2-mm  mesh sieve.  Weigh both the rock fragments and the
         less than 2-mm fine earth fraction.  Record the weights as mrt and m(f, respectively.

 11.4.2  Assumptions


The following assumptions are made in this procedure:


         •  The weight  of each field-applied saran coating is equivalent to each coating applied
            in the laboratory.

         •  Saran has not infiltrated the clod.


         •  The specific gravity of air-dried saran is 1.30 g/cm3.

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                                                                            Section 11.0
                                                                            Revision 4
                                                                            Date:  5/86
                                                                            Page 5 of 5
        • Saran loses 15 percent of its weight upon oven-drying for 48 hours.
        • The density of the rock fragments is 2.65 g/cm3.
11.4.3  Calculations
11.4.3.1  Calculate the weight of the  saran coatings before oven-drying;
                           /[number of coats (final clod wt - initial clod wt)]
        Weight of saran -	—    .    _    ~~
                           \        [(number of coats in lab) -  1]
11.4.3.2  Calculate the weight of the  saran coating after oven-drying:
        OD Weight of saran  =  (0.85)  (Weight of saran)
11.4.3.3  Calculate the volume of the saran coatings:
                                  \
                       Wt of saran
         Saran vol
                           1.30
11.4.3.4  Calculate the volume of water displaced by the clod:
                             Wt of water
         Vol of water  =
                           (density of water)
 11.4.3.5  Calculate the volume of rock fragments in the clod:
                       'wtof RF
         Vol of RF =
                          2.65
 11.4.3.6  Calculate the volume of the less than 2-mm fraction and pore space:
         Vol of fines =  [Vol of water - (Vol of RF + Vol of saran)] and pores
 11.4.3.7  Finally, calculate the field moist bulk density:
                           [OD clod wt -  (wt of RF + OD saran wt)]
         Bulk Density =
                                     Vol of fines and pores

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                                                                         Section 12.0
                                                                         Revision 4
                                                                         Date: 5/86
                                                                         Page 1 of 1
12.0  References

     1.  USDA/SCS.  1983.  National Soils Handbook.  Part 600-606.  U.S. Government Printing
        Office, Washington D.C.

     2.  USDA/SCS.  1984.  SCS National Soil Survey Manual. U.S. Government Printing Office,
        Washington D.C.

     3  Mausbach, M., R. Yeck, D. Nettleton, and W. Lynn.  1983. Principles and Procedures for
        Using Soil Survey Laboratory Data. National Soil Survey Laboratory. Lincoln, Nebraska.

     4.  USDA/SCS.  1981.  National Handbook of Plant Names. U.S. Government Printing Office,
        Washington, D.C.

     5  USDA/SCS  1984b.  Soil Survey Laboratory Methods and Procedures for Collecting Soil
        Samples.  Soil Survey Investigations Report No.  1. U.S.  Government Printing Office,
        Washington D.C.

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